diff --git a/Android/build.gradle b/Android/build.gradle
index b9a1cbf607..2c366965b0 100644
--- a/Android/build.gradle
+++ b/Android/build.gradle
@@ -1,18 +1,18 @@
 apply plugin: 'com.android.application'
 
 dependencies {
-    compile 'com.google.android.gms:play-services-maps:7.0.0'
-    compile 'com.google.android.gms:play-services-location:7.0.0'
-    compile 'com.google.android.gms:play-services-analytics:7.0.0'
+    compile 'com.google.android.gms:play-services-maps:7.3.0'
+    compile 'com.google.android.gms:play-services-location:7.3.0'
+    compile 'com.google.android.gms:play-services-analytics:7.3.0'
 
     compile 'com.sothree.slidinguppanel:library:2.0.2'
 
-    compile 'com.android.support:support-v4:22.1.0'
-    compile 'com.android.support:appcompat-v7:22.1.0'
+    compile 'com.android.support:support-v4:22.1.1'
+    compile 'com.android.support:appcompat-v7:22.1.1'
     compile 'com.android.support:cardview-v7:22.1.0'
     compile 'com.android.support:recyclerview-v7:22.1.0'
 
-    compile 'com.o3dr.android:dronekit-android:2.3.11'
+    compile 'com.o3dr.android:dronekit-android:2.3.25'
 
     compile 'me.grantland:autofittextview:0.2.1'
     compile(name:'shimmer-android-release', ext:'aar')
@@ -22,6 +22,9 @@ dependencies {
     compile files('libs/protobuf-java-2.5.0.jar')
     compile files('libs/jeromq-0.3.4.jar')
     compile files('libs/sius-0.3.2-SNAPSHOT.jar')
+
+    compile 'com.squareup.okhttp:okhttp:2.3.0'
+    compile 'com.squareup.okhttp:okhttp-urlconnection:2.3.0'
 }
 
 android {
diff --git a/Android/res/values/preferences_keys.xml b/Android/res/values/preferences_keys.xml
index d8854014a9..bfa3b4e3d4 100644
--- a/Android/res/values/preferences_keys.xml
+++ b/Android/res/values/preferences_keys.xml
@@ -64,4 +64,8 @@ This file is used to store the preferences keys so that it's accessible and modi
     <string name="pref_udp_ping_receiver_ip_key" translatable="false">pref_udp_ping_receiver_ip</string>
     <string name="pref_udp_ping_receiver_port_key" translatable="false">pref_udp_ping_receiver_port</string>
 
+    <string name="pref_alt_max_value_key" translatable="false">pref_alt_max_value</string>
+    <string name="pref_alt_min_value_key" translatable="false">pref_alt_min_value</string>
+    <string name="pref_alt_default_value_key" translatable="false">pref_alt_default_value</string>
+
 </resources>
diff --git a/Android/res/values/strings.xml b/Android/res/values/strings.xml
index 608cc4ff3c..b27a357ee0 100644
--- a/Android/res/values/strings.xml
+++ b/Android/res/values/strings.xml
@@ -549,5 +549,12 @@
     <string name="pref_udp_server_ping_summary">Enable to allow the app to periodically ping the udp server.</string>
     <string name="pref_udp_ping_receiver_ip_title">UDP ping receiver ip</string>
     <string name="pref_udp_ping_receiver_port_title">UDP ping receiver port</string>
+    <string name="invalid_location_settings_warning">Unable to get accurate location. Please update your location settings!</string>
+
+    <!-- Altitude preferences -->
+    <string name="pref_alt_title">Altitude Preferences</string>
+    <string name="pref_max_alt_title">Max altitude value</string>
+    <string name="pref_min_alt_title">Min altitude value</string>
+    <string name="pref_default_alt_title">Default altitude value</string>
 
 </resources>
diff --git a/Android/res/xml/preferences.xml b/Android/res/xml/preferences.xml
index 3b1284e201..64fa776c05 100644
--- a/Android/res/xml/preferences.xml
+++ b/Android/res/xml/preferences.xml
@@ -282,6 +282,33 @@
                     android:title="@string/pref_ui_gps_hdop_title" />
             </PreferenceCategory>
 
+            <PreferenceCategory
+                android:title="@string/pref_alt_title">
+
+                <EditTextPreference
+                    android:gravity="center"
+                    android:inputType="numberSigned"
+                    android:key="@string/pref_alt_max_value_key"
+                    android:title="@string/pref_max_alt_title"
+                    android:persistent="false"
+                    />
+
+                <EditTextPreference
+                    android:gravity="center"
+                    android:inputType="numberSigned"
+                    android:key="@string/pref_alt_min_value_key"
+                    android:title="@string/pref_min_alt_title"
+                    android:persistent="false"/>
+
+                <EditTextPreference
+                    android:gravity="center"
+                    android:inputType="numberSigned"
+                    android:key="@string/pref_alt_default_value_key"
+                    android:title="@string/pref_default_alt_title"
+                    android:persistent="false"/>
+
+            </PreferenceCategory>
+
             <!-- Disabling kill switch until arducopter v3.3 is out.
             <PreferenceCategory
                 android:title="@string/pref_advance_menu_title">
diff --git a/Android/src/org/droidplanner/android/DroidPlannerApp.java b/Android/src/org/droidplanner/android/DroidPlannerApp.java
index 827b1b2439..75e57b5e08 100644
--- a/Android/src/org/droidplanner/android/DroidPlannerApp.java
+++ b/Android/src/org/droidplanner/android/DroidPlannerApp.java
@@ -23,6 +23,7 @@
 import com.o3dr.services.android.lib.drone.connection.DroneSharePrefs;
 
 import org.droidplanner.android.activities.helpers.BluetoothDevicesActivity;
+import org.droidplanner.android.maps.providers.mapbox.offline.MapDownloader;
 import org.droidplanner.android.notifications.NotificationHandler;
 import org.droidplanner.android.proxy.mission.MissionProxy;
 import org.droidplanner.android.utils.Utils;
@@ -127,6 +128,7 @@ public void run() {
     private DroidPlannerPrefs dpPrefs;
     private LocalBroadcastManager lbm;
     private NotificationHandler notificationHandler;
+    private MapDownloader mapDownloader;
 
     @Override
     public void onCreate() {
@@ -135,9 +137,10 @@ public void onCreate() {
 
         dpPrefs = new DroidPlannerPrefs(context);
         lbm = LocalBroadcastManager.getInstance(context);
+        mapDownloader = new MapDownloader(context);
 
         controlTower = new ControlTower(context);
-        drone = new Drone();
+        drone = new Drone(context);
         missionProxy = new MissionProxy(context, this.drone);
 
         final Thread.UncaughtExceptionHandler dpExceptionHandler = new Thread.UncaughtExceptionHandler() {
@@ -160,6 +163,10 @@ public void uncaughtException(Thread thread, Throwable ex) {
         registerReceiver(broadcastReceiver, intentFilter);
     }
 
+    public MapDownloader getMapDownloader() {
+        return mapDownloader;
+    }
+
     public void addApiListener(ApiListener listener) {
         if (listener == null)
             return;
diff --git a/Android/src/org/droidplanner/android/activities/DrawerNavigationUI.java b/Android/src/org/droidplanner/android/activities/DrawerNavigationUI.java
index 1c037ff483..d41c6a7a85 100644
--- a/Android/src/org/droidplanner/android/activities/DrawerNavigationUI.java
+++ b/Android/src/org/droidplanner/android/activities/DrawerNavigationUI.java
@@ -21,13 +21,11 @@
 import android.widget.FrameLayout;
 import android.widget.TextView;
 
-import com.google.android.gms.maps.GoogleMap;
-
 import org.droidplanner.android.R;
 import org.droidplanner.android.activities.helpers.SuperUI;
 import org.droidplanner.android.fragments.SettingsFragment;
 import org.droidplanner.android.fragments.actionbar.ActionBarTelemFragment;
-import org.droidplanner.android.maps.providers.google_map.GoogleMapFragment;
+import org.droidplanner.android.fragments.control.BaseFlightControlFragment;
 import org.droidplanner.android.widgets.SlidingDrawer;
 
 /**
@@ -100,7 +98,7 @@ protected View getActionDrawer() {
     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data){
         switch(requestCode) {
-            case GoogleMapFragment.REQUEST_CHECK_SETTINGS:
+            case BaseFlightControlFragment.FOLLOW_SETTINGS_UPDATE:
                 LocalBroadcastManager.getInstance(getApplicationContext())
                         .sendBroadcast(new Intent(SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED)
                                 .putExtra(SettingsFragment.EXTRA_RESULT_CODE, resultCode));
diff --git a/Android/src/org/droidplanner/android/activities/EditorActivity.java b/Android/src/org/droidplanner/android/activities/EditorActivity.java
index 58f91fefea..6ba5bb5888 100644
--- a/Android/src/org/droidplanner/android/activities/EditorActivity.java
+++ b/Android/src/org/droidplanner/android/activities/EditorActivity.java
@@ -69,7 +69,7 @@ public class EditorActivity extends DrawerNavigationUI implements OnPathFinished
     static {
         eventFilter.addAction(MissionProxy.ACTION_MISSION_PROXY_UPDATE);
         eventFilter.addAction(AttributeEvent.MISSION_RECEIVED);
-        eventFilter.addAction(AttributeEvent.PARAMETERS_REFRESH_ENDED);
+        eventFilter.addAction(AttributeEvent.PARAMETERS_REFRESH_COMPLETED);
     }
 
     private final BroadcastReceiver eventReceiver = new BroadcastReceiver() {
@@ -77,7 +77,7 @@ public class EditorActivity extends DrawerNavigationUI implements OnPathFinished
         public void onReceive(Context context, Intent intent) {
             final String action = intent.getAction();
             switch (action) {
-                case AttributeEvent.PARAMETERS_REFRESH_ENDED:
+                case AttributeEvent.PARAMETERS_REFRESH_COMPLETED:
                 case MissionProxy.ACTION_MISSION_PROXY_UPDATE:
                     updateMissionLength();
                     break;
diff --git a/Android/src/org/droidplanner/android/data/DatabaseState.java b/Android/src/org/droidplanner/android/data/DatabaseState.java
new file mode 100644
index 0000000000..9eddc4d323
--- /dev/null
+++ b/Android/src/org/droidplanner/android/data/DatabaseState.java
@@ -0,0 +1,40 @@
+package org.droidplanner.android.data;
+
+import android.content.Context;
+import android.text.TextUtils;
+
+import org.droidplanner.android.maps.providers.mapbox.offline.OfflineDatabaseHandler;
+
+import java.util.Locale;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/13/15.
+ */
+public class DatabaseState {
+
+    private static final ConcurrentHashMap<String, OfflineDatabaseHandler> databaseHandlers = new ConcurrentHashMap<>();
+
+    public static OfflineDatabaseHandler getOfflineDatabaseHandlerForMapId(Context context, String dbName) {
+        final String lowerMapId = dbName.toLowerCase(Locale.US);
+        if (databaseHandlers.containsKey(lowerMapId)) {
+            return databaseHandlers.get(dbName);
+        }
+
+        OfflineDatabaseHandler dbh = new OfflineDatabaseHandler(context, lowerMapId);
+        databaseHandlers.put(lowerMapId, dbh);
+        return dbh;
+    }
+
+    public static void deleteDatabase(Context context, String dbName){
+        if(context == null || TextUtils.isEmpty(dbName))
+            return;
+
+        final String lowerMapId = dbName.toLowerCase(Locale.US);
+        OfflineDatabaseHandler dbHandler = databaseHandlers.remove(lowerMapId);
+        if(dbHandler != null)
+            dbHandler.close();
+
+        context.deleteDatabase(lowerMapId);
+    }
+}
diff --git a/Android/src/org/droidplanner/android/dialogs/EditInputDialog.java b/Android/src/org/droidplanner/android/dialogs/EditInputDialog.java
index 66fd9cd76e..5e991962d4 100644
--- a/Android/src/org/droidplanner/android/dialogs/EditInputDialog.java
+++ b/Android/src/org/droidplanner/android/dialogs/EditInputDialog.java
@@ -1,9 +1,9 @@
 package org.droidplanner.android.dialogs;
 
-import android.app.AlertDialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.os.Bundle;
+import android.support.v7.app.AlertDialog;
 import android.text.TextUtils;
 import android.view.View;
 import android.widget.EditText;
diff --git a/Android/src/org/droidplanner/android/dialogs/YesNoDialog.java b/Android/src/org/droidplanner/android/dialogs/YesNoDialog.java
index 9e1e7aa258..0bdbc19281 100644
--- a/Android/src/org/droidplanner/android/dialogs/YesNoDialog.java
+++ b/Android/src/org/droidplanner/android/dialogs/YesNoDialog.java
@@ -1,11 +1,11 @@
 package org.droidplanner.android.dialogs;
 
-import android.app.AlertDialog;
 import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.os.Bundle;
 import android.support.v4.app.DialogFragment;
+import android.support.v7.app.AlertDialog;
 import android.view.View;
 import android.widget.TextView;
 
@@ -69,8 +69,7 @@ public void onClick(DialogInterface dialog, int which) {
     }
 
     protected View generateContentView(Bundle savedInstanceState){
-        final View contentView = getActivity().getLayoutInflater().inflate(R.layout
-                .dialog_yes_no_content, null);
+        final View contentView = getActivity().getLayoutInflater().inflate(R.layout.dialog_yes_no_content, null);
 
         if(contentView == null){
             return contentView;
diff --git a/Android/src/org/droidplanner/android/dialogs/YesNoWithPrefsDialog.java b/Android/src/org/droidplanner/android/dialogs/YesNoWithPrefsDialog.java
index 4c2c9c888f..8d5caaf059 100644
--- a/Android/src/org/droidplanner/android/dialogs/YesNoWithPrefsDialog.java
+++ b/Android/src/org/droidplanner/android/dialogs/YesNoWithPrefsDialog.java
@@ -1,11 +1,11 @@
 package org.droidplanner.android.dialogs;
 
-import android.app.AlertDialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.preference.Preference;
+import android.support.v7.app.AlertDialog;
 import android.view.View;
 import android.widget.CheckBox;
 import android.widget.Toast;
diff --git a/Android/src/org/droidplanner/android/fragments/DroneMap.java b/Android/src/org/droidplanner/android/fragments/DroneMap.java
index 95bece9f3e..bae543de17 100644
--- a/Android/src/org/droidplanner/android/fragments/DroneMap.java
+++ b/Android/src/org/droidplanner/android/fragments/DroneMap.java
@@ -56,6 +56,7 @@ public abstract class DroneMap extends ApiListenerFragment {
 		eventFilter.addAction(AttributeEvent.STATE_DISCONNECTED);
 		eventFilter.addAction(AttributeEvent.CAMERA_FOOTPRINTS_UPDATED);
 		eventFilter.addAction(AttributeEvent.ATTITUDE_UPDATED);
+		eventFilter.addAction(AttributeEvent.HOME_UPDATED);
         eventFilter.addAction(ACTION_UPDATE_MAP);
 	}
 
@@ -70,6 +71,7 @@ public void onReceive(Context context, Intent intent) {
 			final String action = intent.getAction();
             switch (action) {
                 case ACTION_UPDATE_MAP:
+				case AttributeEvent.HOME_UPDATED:
                 case MissionProxy.ACTION_MISSION_PROXY_UPDATE:
                     postUpdate();
                     break;
diff --git a/Android/src/org/droidplanner/android/fragments/ParamsFragment.java b/Android/src/org/droidplanner/android/fragments/ParamsFragment.java
index 18968ca4a4..6d53de8c27 100644
--- a/Android/src/org/droidplanner/android/fragments/ParamsFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/ParamsFragment.java
@@ -63,8 +63,8 @@ public class ParamsFragment extends ApiListenerListFragment {
 
     static {
         intentFilter.addAction(AttributeEvent.PARAMETERS_REFRESH_STARTED);
-        intentFilter.addAction(AttributeEvent.PARAMETERS_REFRESH_ENDED);
-        intentFilter.addAction(AttributeEvent.PARAMETERS_RECEIVED);
+        intentFilter.addAction(AttributeEvent.PARAMETERS_REFRESH_COMPLETED);
+        intentFilter.addAction(AttributeEvent.PARAMETER_RECEIVED);
         intentFilter.addAction(AttributeEvent.STATE_CONNECTED);
         intentFilter.addAction(AttributeEvent.TYPE_UPDATED);
     }
@@ -78,7 +78,7 @@ public void onReceive(Context context, Intent intent) {
                     startProgress();
                     break;
 
-                case AttributeEvent.PARAMETERS_REFRESH_ENDED:
+                case AttributeEvent.PARAMETERS_REFRESH_COMPLETED:
                     stopProgress();
                     /*** FALL - THROUGH ***/
                 case AttributeEvent.STATE_CONNECTED:
@@ -90,7 +90,7 @@ public void onReceive(Context context, Intent intent) {
                     }
                     break;
 
-                case AttributeEvent.PARAMETERS_RECEIVED:
+                case AttributeEvent.PARAMETER_RECEIVED:
                     final int defaultValue = -1;
                     int index = intent.getIntExtra(AttributeEventExtra.EXTRA_PARAMETER_INDEX, defaultValue);
                     int count = intent.getIntExtra(AttributeEventExtra.EXTRA_PARAMETERS_COUNT, defaultValue);
diff --git a/Android/src/org/droidplanner/android/fragments/SensorSetupFragment.java b/Android/src/org/droidplanner/android/fragments/SensorSetupFragment.java
index 365d6a091f..4da36266e8 100644
--- a/Android/src/org/droidplanner/android/fragments/SensorSetupFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/SensorSetupFragment.java
@@ -12,7 +12,6 @@
 
 import org.droidplanner.android.R;
 import org.droidplanner.android.fragments.calibration.imu.FragmentSetupIMU;
-import org.droidplanner.android.fragments.calibration.mag.FragmentSetupMAG;
 import org.droidplanner.android.widgets.viewPager.TabPageIndicator;
 
 /**
@@ -54,15 +53,11 @@ public Fragment getItem(int i) {
                 case 0:
                 default:
                     return new FragmentSetupIMU();
-                case 1:
-                    return new FragmentSetupMAG();
             }
         }
 
         @Override
         public int getCount() {
-            //Enable mag calibration when it's fully working.
-//            return 2;
             return 1;
         }
 
@@ -72,8 +67,6 @@ public CharSequence getPageTitle(int position) {
                 case 0:
                 default:
                     return FragmentSetupIMU.getTitle(context);
-                case 1:
-                    return FragmentSetupMAG.getTitle(context);
             }
         }
     }
diff --git a/Android/src/org/droidplanner/android/fragments/SettingsFragment.java b/Android/src/org/droidplanner/android/fragments/SettingsFragment.java
index 68a13d2c54..e8c0cace2e 100644
--- a/Android/src/org/droidplanner/android/fragments/SettingsFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/SettingsFragment.java
@@ -11,10 +11,12 @@
 import android.os.Bundle;
 import android.os.Handler;
 import android.preference.CheckBoxPreference;
+import android.preference.EditTextPreference;
 import android.preference.ListPreference;
 import android.preference.Preference;
 import android.preference.PreferenceCategory;
 import android.preference.PreferenceFragment;
+import android.support.annotation.StringRes;
 import android.support.v4.content.LocalBroadcastManager;
 import android.text.TextUtils;
 import android.util.Log;
@@ -29,6 +31,7 @@
 import com.o3dr.services.android.lib.drone.property.State;
 import com.o3dr.services.android.lib.drone.property.Type;
 
+import org.beyene.sius.unit.length.LengthUnit;
 import org.droidplanner.android.DroidPlannerApp;
 import org.droidplanner.android.R;
 import org.droidplanner.android.activities.helpers.MapPreferencesActivity;
@@ -38,6 +41,9 @@
 import org.droidplanner.android.utils.analytics.GAUtils;
 import org.droidplanner.android.utils.file.DirectoryPath;
 import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
+import org.droidplanner.android.utils.unit.UnitManager;
+import org.droidplanner.android.utils.unit.providers.length.LengthUnitProvider;
+import org.droidplanner.android.utils.unit.systems.UnitSystem;
 
 import java.util.HashSet;
 import java.util.Locale;
@@ -96,6 +102,7 @@ public class SettingsFragment extends PreferenceFragment implements OnSharedPref
         intentFilter.addAction(AttributeEvent.HEARTBEAT_FIRST);
         intentFilter.addAction(AttributeEvent.HEARTBEAT_RESTORED);
         intentFilter.addAction(AttributeEvent.TYPE_UPDATED);
+        intentFilter.addAction(ACTION_PREF_UNIT_SYSTEM_UPDATE);
     }
 
     private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
@@ -130,6 +137,10 @@ public void onReceive(Context context, Intent intent) {
                     } else
                         updateFirmwareVersionPreference(null);
                     break;
+
+                case ACTION_PREF_UNIT_SYSTEM_UPDATE:
+                    setupAltitudePreferences();
+                    break;
             }
         }
     };
@@ -248,6 +259,7 @@ public boolean onPreferenceChange(Preference preference, Object newValue) {
         setupBluetoothDevicePreferences();
         setupImminentGroundCollisionWarningPreference();
         setupMapPreferences();
+        setupAltitudePreferences();
     }
 
     private void setupAdvancedMenu(){
@@ -368,7 +380,7 @@ private void setupBluetoothDevicePreferences(){
             preference.setOnResultListener(new ClearBTDialogPreference.OnResultListener() {
                 @Override
                 public void onResult(boolean result) {
-                    if(result){
+                    if (result) {
                         updateBluetoothDevicePreference(preference, dpPrefs.getBluetoothDeviceAddress());
                     }
                 }
@@ -376,6 +388,49 @@ public void onResult(boolean result) {
         }
     }
 
+    private void setupAltitudePreferences(){
+        setupAltitudePreferenceHelper(R.string.pref_alt_max_value_key, dpPrefs.getMaxAltitude());
+        setupAltitudePreferenceHelper(R.string.pref_alt_min_value_key, dpPrefs.getMinAltitude());
+        setupAltitudePreferenceHelper(R.string.pref_alt_default_value_key, dpPrefs.getDefaultAltitude());
+    }
+
+    private void setupAltitudePreferenceHelper(final @StringRes int prefKeyRes, int defaultAlt){
+        final LengthUnitProvider lup = getLengthUnitProvider();
+
+        final EditTextPreference altPref = (EditTextPreference) findPreference(getString(prefKeyRes));
+        if(altPref != null){
+            final LengthUnit altValue = lup.boxBaseValueToTarget(defaultAlt);
+
+            altPref.setText(String.valueOf((int) altValue.getValue()));
+            altPref.setSummary(altValue.toString());
+
+            altPref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
+                @Override
+                public boolean onPreferenceChange(Preference preference, Object newValue) {
+                    try {
+                        final int altValue = Integer.parseInt(newValue.toString());
+
+                        final LengthUnitProvider lup = getLengthUnitProvider();
+                        final LengthUnit newAltValue = lup.boxTargetValue(altValue);
+
+                        altPref.setText(String.valueOf((int) newAltValue.getValue()));
+                        altPref.setSummary(newAltValue.toString());
+
+                        dpPrefs.setAltitudePreference(prefKeyRes, (int) lup.fromTargetToBase(newAltValue).getValue());
+                    } catch (NumberFormatException e) {
+
+                    }
+                    return false;
+                }
+            });
+        }
+    }
+
+    private LengthUnitProvider getLengthUnitProvider(){
+        final UnitSystem unitSystem = UnitManager.getUnitSystem(getActivity().getApplicationContext());
+        return unitSystem.getLengthUnitProvider();
+    }
+
     private void updateBluetoothDevicePreference(Preference preference, String deviceAddress){
         if(TextUtils.isEmpty(deviceAddress)) {
             preference.setEnabled(false);
diff --git a/Android/src/org/droidplanner/android/fragments/TelemetryFragment.java b/Android/src/org/droidplanner/android/fragments/TelemetryFragment.java
index d350ebf866..7f91ee716b 100644
--- a/Android/src/org/droidplanner/android/fragments/TelemetryFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/TelemetryFragment.java
@@ -38,6 +38,7 @@ public class TelemetryFragment extends ApiListenerFragment {
     static {
         eventFilter.addAction(AttributeEvent.ATTITUDE_UPDATED);
         eventFilter.addAction(AttributeEvent.SPEED_UPDATED);
+        eventFilter.addAction(AttributeEvent.ALTITUDE_UPDATED);
         eventFilter.addAction(AttributeEvent.STATE_UPDATED);
     }
 
@@ -62,7 +63,9 @@ public void onReceive(Context context, Intent intent) {
                 case AttributeEvent.SPEED_UPDATED:
                     final Speed droneSpeed = drone.getAttribute(AttributeType.SPEED);
                     onSpeedUpdate(droneSpeed);
+                    break;
 
+                case AttributeEvent.ALTITUDE_UPDATED:
                     final Altitude droneAltitude = drone.getAttribute(AttributeType.ALTITUDE);
                     onAltitudeUpdate(droneAltitude);
                     break;
diff --git a/Android/src/org/droidplanner/android/fragments/calibration/mag/FragmentSetupMAG.java b/Android/src/org/droidplanner/android/fragments/calibration/mag/FragmentSetupMAG.java
deleted file mode 100644
index 6c58f76c77..0000000000
--- a/Android/src/org/droidplanner/android/fragments/calibration/mag/FragmentSetupMAG.java
+++ /dev/null
@@ -1,336 +0,0 @@
-package org.droidplanner.android.fragments.calibration.mag;
-
-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
-import android.os.Bundle;
-import android.util.Log;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.Button;
-import android.widget.ProgressBar;
-import android.widget.TextView;
-import android.widget.Toast;
-
-import com.o3dr.android.client.Drone;
-import com.o3dr.services.android.lib.drone.attribute.AttributeEvent;
-import com.o3dr.services.android.lib.drone.attribute.AttributeEventExtra;
-import com.o3dr.services.android.lib.drone.attribute.AttributeType;
-import com.o3dr.services.android.lib.drone.property.State;
-
-import org.droidplanner.android.R;
-import org.droidplanner.android.fragments.helpers.ApiListenerFragment;
-import org.droidplanner.android.utils.Point3D;
-import org.droidplanner.android.widgets.scatterplot.ScatterPlot;
-
-import java.util.Arrays;
-
-public class FragmentSetupMAG extends ApiListenerFragment {
-
-    private static final int MIN_POINTS_COUNT = 250;
-
-	private static final int CALIBRATION_IDLE = 0;
-	private static final int CALIBRATION_IN_PROGRESS = 1;
-	private static final int CALIBRATION_COMPLETED = 2;
-
-	private static final String EXTRA_CALIBRATION_STATUS = "extra_calibration_status";
-	private static final String EXTRA_CALIBRATION_POINTS = "extra_calibration_points";
-
-	private static final IntentFilter intentFilter = new IntentFilter();
-	static {
-		intentFilter.addAction(AttributeEvent.STATE_CONNECTED);
-		intentFilter.addAction(AttributeEvent.STATE_DISCONNECTED);
-        intentFilter.addAction(AttributeEvent.CALIBRATION_MAG_STARTED);
-        intentFilter.addAction(AttributeEvent.CALIBRATION_MAG_ESTIMATION);
-        intentFilter.addAction(AttributeEvent.CALIBRATION_MAG_COMPLETED);
-	}
-
-	private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
-		@Override
-		public void onReceive(Context context, Intent intent) {
-			final String action = intent.getAction();
-            switch (action) {
-                case AttributeEvent.STATE_CONNECTED:
-                    buttonStep.setEnabled(true);
-                    break;
-                case AttributeEvent.STATE_DISCONNECTED:
-                    cancelCalibration();
-                    buttonStep.setEnabled(false);
-                    break;
-                case AttributeEvent.CALIBRATION_MAG_STARTED: {
-                    double[] pointsX = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_X);
-                    double[] pointsY = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_Y);
-                    double[] pointsZ = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_Z);
-
-                    inProgressPoints = Point3D.fromDoubleArrays(pointsX, pointsY, pointsZ);
-
-                    setCalibrationStatus(CALIBRATION_IN_PROGRESS);
-                    break;
-                }
-                case AttributeEvent.CALIBRATION_MAG_ESTIMATION: {
-                    double[] pointsX = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_X);
-                    double[] pointsY = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_Y);
-                    double[] pointsZ = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_POINTS_Z);
-
-                    inProgressPoints = Point3D.fromDoubleArrays(pointsX, pointsY, pointsZ);
-
-                    final int pointsCount = inProgressPoints == null ? 0 : inProgressPoints.length;
-                    if (pointsCount == 0) {
-                        return;
-                    }
-
-                    final double fitness = intent.getDoubleExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_FITNESS,
-                            0);
-                    final double[] fitCenter = intent.getDoubleArrayExtra(AttributeEventExtra
-                            .EXTRA_CALIBRATION_MAG_FIT_CENTER);
-                    final double[] fitRadii = intent.getDoubleArrayExtra(AttributeEventExtra
-                            .EXTRA_CALIBRATION_MAG_FIT_RADII);
-
-                    if (pointsCount < MIN_POINTS_COUNT) {
-                        calibrationFitness.setIndeterminate(true);
-                        calibrationProgress.setText("0 / 100");
-                    } else {
-                        final int progress = (int) (fitness * 100);
-                        calibrationFitness.setIndeterminate(false);
-                        calibrationFitness.setMax(100);
-                        calibrationFitness.setProgress(progress);
-
-                        calibrationProgress.setText(progress + " / 100");
-                    }
-
-                    // Grab the last point
-                    final Point3D point = inProgressPoints[pointsCount - 1];
-
-                    plot1.addData((float) point.x);
-                    plot1.addData((float) point.z);
-                    if (fitCenter == null || fitRadii == null) {
-                        plot1.updateSphere(null);
-                    } else {
-                        plot1.updateSphere(new int[]{(int) fitCenter[0], (int) fitCenter[2],
-                                (int) fitRadii[0], (int) fitRadii[2]});
-                    }
-                    plot1.invalidate();
-
-                    plot2.addData((float) point.y);
-                    plot2.addData((float) point.z);
-                    if (fitCenter == null || fitRadii == null) {
-                        plot2.updateSphere(null);
-                    } else {
-                        plot2.updateSphere(new int[]{(int) fitCenter[1], (int) fitCenter[2],
-                                (int) fitRadii[1], (int) fitRadii[2]});
-                    }
-                    plot2.invalidate();
-
-                    break;
-                }
-                case AttributeEvent.CALIBRATION_MAG_COMPLETED:
-                    double[] offsets = intent.getDoubleArrayExtra(AttributeEventExtra.EXTRA_CALIBRATION_MAG_OFFSETS);
-                    if (offsets != null) {
-                        String offsetsSummary = Arrays.toString(offsets);
-                        Log.d("MAG", "Calibration Finished: " + offsetsSummary);
-                        Toast.makeText(getActivity(), "Calibration Finished: " + offsetsSummary,
-                                Toast.LENGTH_LONG).show();
-                    }
-
-                    setCalibrationStatus(CALIBRATION_COMPLETED);
-                    break;
-            }
-		}
-	};
-
-	private View inProgressCalibrationView;
-	private Button buttonStep;
-	private TextView calibrationProgress;
-	private ProgressBar calibrationFitness;
-	private ScatterPlot plot1, plot2;
-
-	private int calibrationStatus = CALIBRATION_IDLE;
-
-    private Point3D[] startPoints;
-    private Point3D[] inProgressPoints;
-
-	@Override
-	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
-		return inflater.inflate(R.layout.fragment_setup_mag_main, container, false);
-	}
-
-	@Override
-	public void onViewCreated(View view, Bundle savedInstanceState) {
-		super.onViewCreated(view, savedInstanceState);
-
-		plot1 = (ScatterPlot) view.findViewById(R.id.scatterPlot1);
-		plot1.setTitle("XZ");
-
-		plot2 = (ScatterPlot) view.findViewById(R.id.scatterPlot2);
-		plot2.setTitle("YZ");
-
-		inProgressCalibrationView = view.findViewById(R.id.in_progress_calibration_container);
-
-		calibrationProgress = (TextView) view.findViewById(R.id.calibration_progress);
-
-		buttonStep = (Button) view.findViewById(R.id.buttonStep);
-		buttonStep.setEnabled(false);
-		buttonStep.setOnClickListener(new View.OnClickListener() {
-			@Override
-			public void onClick(View v) {
-				if (calibrationStatus == CALIBRATION_COMPLETED) {
-					// Clear the screen.
-					clearScreen();
-					setCalibrationStatus(CALIBRATION_IDLE);
-				} else {
-					startCalibration();
-				}
-			}
-		});
-
-		Button buttonCancel = (Button) view.findViewById(R.id.buttonCancel);
-		buttonCancel.setOnClickListener(new View.OnClickListener() {
-			@Override
-			public void onClick(View v) {
-				cancelCalibration();
-			}
-		});
-
-		calibrationFitness = (ProgressBar) view.findViewById(R.id.calibration_progress_bar);
-
-		if (savedInstanceState != null) {
-			final int calibrationStatus = savedInstanceState.getInt(EXTRA_CALIBRATION_STATUS,
-					CALIBRATION_IDLE);
-			setCalibrationStatus(calibrationStatus);
-
-			if (calibrationStatus == CALIBRATION_IN_PROGRESS) {
-				final Point3D[] loadedPoints = (Point3D[]) savedInstanceState
-						.getParcelableArray(EXTRA_CALIBRATION_POINTS);
-				if (loadedPoints != null && loadedPoints.length > 0) {
-					startPoints = loadedPoints;
-
-					for (Point3D point : loadedPoints) {
-						final double x = point.x;
-						final double y = point.y;
-						final double z = point.z;
-
-						plot1.addData((float) x);
-						plot1.addData((float) z);
-
-						plot2.addData((float) y);
-						plot2.addData((float) z);
-					}
-
-					plot1.invalidate();
-					plot2.invalidate();
-				}
-			}
-		}
-	}
-
-	@Override
-	public void onSaveInstanceState(Bundle outState) {
-		super.onSaveInstanceState(outState);
-
-		outState.putInt(EXTRA_CALIBRATION_STATUS, calibrationStatus);
-
-		if (getDrone().isConnected() && inProgressPoints != null && inProgressPoints.length > 0){
-				outState.putParcelableArray(EXTRA_CALIBRATION_POINTS, inProgressPoints);
-		}
-	}
-
-	private void pauseCalibration() {
-		if (getDrone().isConnected()) {
-			getDrone().stopMagnetometerCalibration();
-		}
-	}
-
-	private void cancelCalibration() {
-        if (getDrone().isConnected()) {
-            getDrone().stopMagnetometerCalibration();
-			if (calibrationStatus == CALIBRATION_IN_PROGRESS) {
-				setCalibrationStatus(CALIBRATION_IDLE);
-			}
-		}
-		clearScreen();
-	}
-
-	private void clearScreen() {
-		plot1.reset();
-		plot2.reset();
-	}
-
-	private void setCalibrationStatus(int status) {
-		if (calibrationStatus == status) {
-			return;
-		}
-
-		calibrationStatus = status;
-		switch (calibrationStatus) {
-		case CALIBRATION_IN_PROGRESS:
-			// Hide the 'start' button
-			buttonStep.setVisibility(View.GONE);
-
-			// Show the 'in progress view'
-			inProgressCalibrationView.setVisibility(View.VISIBLE);
-			calibrationFitness.setIndeterminate(true);
-			calibrationProgress.setText("0 / 100");
-			break;
-
-		case CALIBRATION_COMPLETED:
-			calibrationFitness.setIndeterminate(false);
-			calibrationFitness.setMax(100);
-			calibrationFitness.setProgress(100);
-
-			// Hide the 'in progress view'
-			inProgressCalibrationView.setVisibility(View.GONE);
-
-			// Show the 'calibrate/done' button
-			buttonStep.setVisibility(View.VISIBLE);
-			buttonStep.setText(R.string.button_setup_done);
-			break;
-
-		default:
-			// Hide the 'in progress view'
-			inProgressCalibrationView.setVisibility(View.GONE);
-
-			// Show the 'calibrate/done' button
-			buttonStep.setVisibility(View.VISIBLE);
-			buttonStep.setText(R.string.button_setup_calibrate);
-			break;
-		}
-	}
-
-	public void startCalibration() {
-		Drone dpApi = getDrone();
-		if (dpApi.isConnected()) {
-            double[][] result = Point3D.fromPoint3Ds(startPoints);
-            dpApi.startMagnetometerCalibration(result[0], result[1], result[2]);
-			startPoints = null;
-		}
-	}
-
-	public static CharSequence getTitle(Context context) {
-		return context.getText(R.string.setup_mag_title);
-	}
-
-	@Override
-	public void onApiConnected() {
-        Drone drone = getDrone();
-        State droneState = drone.getAttribute(AttributeType.STATE);
-		if (droneState.isConnected() && !droneState.isFlying()) {
-			buttonStep.setEnabled(true);
-		} else {
-			cancelCalibration();
-			buttonStep.setEnabled(false);
-		}
-
-		getBroadcastManager().registerReceiver(broadcastReceiver, intentFilter);
-		if (calibrationStatus == CALIBRATION_IN_PROGRESS) {
-			startCalibration();
-		}
-	}
-
-	@Override
-	public void onApiDisconnected() {
-		getBroadcastManager().unregisterReceiver(broadcastReceiver);
-		pauseCalibration();
-	}
-}
diff --git a/Android/src/org/droidplanner/android/fragments/control/BaseFlightControlFragment.java b/Android/src/org/droidplanner/android/fragments/control/BaseFlightControlFragment.java
new file mode 100644
index 0000000000..420bf74112
--- /dev/null
+++ b/Android/src/org/droidplanner/android/fragments/control/BaseFlightControlFragment.java
@@ -0,0 +1,115 @@
+package org.droidplanner.android.fragments.control;
+
+import android.app.Activity;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.view.View;
+import android.widget.Toast;
+
+import com.google.android.gms.location.LocationRequest;
+import com.o3dr.android.client.Drone;
+import com.o3dr.services.android.lib.drone.attribute.AttributeType;
+import com.o3dr.services.android.lib.gcs.follow.FollowState;
+import com.o3dr.services.android.lib.gcs.follow.FollowType;
+
+import org.droidplanner.android.activities.DrawerNavigationUI;
+import org.droidplanner.android.fragments.SettingsFragment;
+import org.droidplanner.android.fragments.helpers.ApiListenerFragment;
+import org.droidplanner.android.utils.location.CheckLocationSettings;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/25/15.
+ */
+public abstract class BaseFlightControlFragment extends ApiListenerFragment implements View.OnClickListener,
+        FlightControlManagerFragment.SlidingUpHeader {
+
+    public static final int FOLLOW_SETTINGS_UPDATE = 147;
+
+    private static final String TAG = BaseFlightControlFragment.class.getSimpleName();
+
+    private static final int FOLLOW_LOCATION_PRIORITY = LocationRequest.PRIORITY_HIGH_ACCURACY;
+    private static final long FOLLOW_LOCATION_UPDATE_INTERVAL = 30000; // ms
+    private static final long FOLLOW_LOCATION_UPDATE_FASTEST_INTERVAL = 5000; // ms
+    private static final float FOLLOW_LOCATION_UPDATE_MIN_DISPLACEMENT = 0; // m
+
+    private static final IntentFilter filter = new IntentFilter(SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED);
+
+    private final BroadcastReceiver receiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            switch(intent.getAction()){
+                case SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED:
+                    final int resultCode = intent.getIntExtra(SettingsFragment.EXTRA_RESULT_CODE, Activity.RESULT_OK);
+                    switch (resultCode) {
+                        case Activity.RESULT_OK:
+                            // All required changes were successfully made. Enable follow me.
+                            enableFollowMe(getDrone());
+                            break;
+
+                        case Activity.RESULT_CANCELED:
+                            // The user was asked to change settings, but chose not to
+                            Toast.makeText(getActivity(), "Please update your location settings!", Toast.LENGTH_LONG).show();
+                            break;
+                        default:
+                            break;
+                    }
+                    break;
+            }
+        }
+    };
+
+    @Override
+    public void onAttach(Activity activity){
+        super.onAttach(activity);
+        if(!(activity instanceof DrawerNavigationUI)){
+            throw new IllegalStateException("Parent activity must be an instance of " + DrawerNavigationUI.class
+                    .getName());
+        }
+    }
+
+    @Override
+    public void onApiConnected(){
+        getBroadcastManager().registerReceiver(receiver, filter);
+    }
+
+    @Override
+    public void onApiDisconnected(){
+        getBroadcastManager().unregisterReceiver(receiver);
+    }
+
+    protected void toggleFollowMe() {
+        final Drone drone = getDrone();
+        if (drone == null)
+            return;
+
+        final FollowState followState = drone.getAttribute(AttributeType.FOLLOW_STATE);
+        if (followState.isEnabled()) {
+            drone.disableFollowMe();
+        } else {
+            enableFollowMe(drone);
+        }
+    }
+
+    private void enableFollowMe(final Drone drone) {
+        if(drone == null)
+            return;
+
+        final LocationRequest locationReq = LocationRequest.create()
+                .setPriority(FOLLOW_LOCATION_PRIORITY)
+                .setFastestInterval(FOLLOW_LOCATION_UPDATE_FASTEST_INTERVAL)
+                .setInterval(FOLLOW_LOCATION_UPDATE_INTERVAL)
+                .setSmallestDisplacement(FOLLOW_LOCATION_UPDATE_MIN_DISPLACEMENT);
+
+        final CheckLocationSettings locationSettingsChecker = new CheckLocationSettings((DrawerNavigationUI) getActivity(), locationReq,
+                new Runnable() {
+                    @Override
+                    public void run() {
+                        drone.enableFollowMe(FollowType.LEASH);
+                    }
+                });
+
+        locationSettingsChecker.check();
+    }
+}
diff --git a/Android/src/org/droidplanner/android/fragments/control/CopterFlightControlFragment.java b/Android/src/org/droidplanner/android/fragments/control/CopterFlightControlFragment.java
index 0e34d7275a..36918b4652 100644
--- a/Android/src/org/droidplanner/android/fragments/control/CopterFlightControlFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/control/CopterFlightControlFragment.java
@@ -36,13 +36,11 @@
 /**
  * Provide functionality for flight action button specific to copters.
  */
-public class CopterFlightControlFragment extends ApiListenerFragment implements View.OnClickListener,
-        FlightControlManagerFragment.SlidingUpHeader {
+public class CopterFlightControlFragment extends BaseFlightControlFragment {
 
     private static final String TAG = CopterFlightControlFragment.class.getSimpleName();
 
     private static final String ACTION_FLIGHT_ACTION_BUTTON = "Copter flight action button";
-    private static final double TAKEOFF_ALTITUDE = 10.0;
 
     private static final IntentFilter eventFilter = new IntentFilter();
 
@@ -203,6 +201,7 @@ public void onViewCreated(View view, Bundle savedInstanceState) {
 
     @Override
     public void onApiConnected() {
+        super.onApiConnected();
         missionProxy = getMissionProxy();
 
         setupButtonsByFlightState();
@@ -214,6 +213,7 @@ public void onApiConnected() {
 
     @Override
     public void onApiDisconnected() {
+        super.onApiDisconnected();
         getBroadcastManager().unregisterReceiver(eventReceiver);
     }
 
@@ -277,13 +277,7 @@ public void onClick(View v) {
                 break;
 
             case R.id.mc_follow:
-                FollowState followState = drone.getAttribute(AttributeType.FOLLOW_STATE);
-                if (followState != null) {
-                    if (followState.isEnabled())
-                        drone.disableFollowMe();
-                    else
-                        drone.enableFollowMe(FollowType.LEASH);
-                }
+                toggleFollowMe();
                 break;
 
             case R.id.mc_dronieBtn:
@@ -325,7 +319,8 @@ private void getTakeOffConfirmation(){
         final SlideToUnlockDialog unlockDialog = SlideToUnlockDialog.newInstance("take off", new Runnable() {
             @Override
             public void run() {
-                getDrone().doGuidedTakeoff(TAKEOFF_ALTITUDE);
+                final int takeOffAltitude = getAppPrefs().getDefaultAltitude();
+                getDrone().doGuidedTakeoff(takeOffAltitude);
             }
         });
         unlockDialog.show(getChildFragmentManager(), "Slide to take off");
@@ -335,8 +330,11 @@ private void getTakeOffInAutoConfirmation() {
         final SlideToUnlockDialog unlockDialog = SlideToUnlockDialog.newInstance("take off in auto", new Runnable() {
             @Override
             public void run() {
+
+                final int takeOffAltitude = getAppPrefs().getDefaultAltitude();
+
                 Drone drone = getDrone();
-                drone.doGuidedTakeoff(TAKEOFF_ALTITUDE);
+                drone.doGuidedTakeoff(takeOffAltitude);
                 drone.changeVehicleMode(VehicleMode.COPTER_AUTO);
             }
         });
diff --git a/Android/src/org/droidplanner/android/fragments/control/FlightControlManagerFragment.java b/Android/src/org/droidplanner/android/fragments/control/FlightControlManagerFragment.java
index 6f4775f78e..968bfac8a4 100644
--- a/Android/src/org/droidplanner/android/fragments/control/FlightControlManagerFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/control/FlightControlManagerFragment.java
@@ -94,7 +94,7 @@ private void selectActionsBar(int droneType) {
 			break;
 		}
 
-		fm.beginTransaction().replace(R.id.flight_actions_bar, actionsBarFragment).commit();
+		fm.beginTransaction().replace(R.id.flight_actions_bar, actionsBarFragment).commitAllowingStateLoss();
 		header = (SlidingUpHeader) actionsBarFragment;
 	}
 
diff --git a/Android/src/org/droidplanner/android/fragments/control/GenericActionsFragment.java b/Android/src/org/droidplanner/android/fragments/control/GenericActionsFragment.java
index 21c867b8b7..4750e63428 100644
--- a/Android/src/org/droidplanner/android/fragments/control/GenericActionsFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/control/GenericActionsFragment.java
@@ -16,8 +16,7 @@
 /**
  * Provides action buttons functionality for generic drone type.
  */
-public class GenericActionsFragment extends Fragment implements View.OnClickListener,
-        FlightControlManagerFragment.SlidingUpHeader {
+public class GenericActionsFragment extends BaseFlightControlFragment {
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
diff --git a/Android/src/org/droidplanner/android/fragments/control/PlaneFlightControlFragment.java b/Android/src/org/droidplanner/android/fragments/control/PlaneFlightControlFragment.java
index 489f279957..041f0cf54c 100644
--- a/Android/src/org/droidplanner/android/fragments/control/PlaneFlightControlFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/control/PlaneFlightControlFragment.java
@@ -33,8 +33,7 @@
 /**
  * Provides functionality for flight action buttons specific to planes.
  */
-public class PlaneFlightControlFragment extends ApiListenerFragment implements
-        View.OnClickListener, FlightControlManagerFragment.SlidingUpHeader {
+public class PlaneFlightControlFragment extends BaseFlightControlFragment {
 
     private static final String ACTION_FLIGHT_ACTION_BUTTON = "Copter flight action button";
 
@@ -270,6 +269,8 @@ private void setupButtonsForFlying() {
 
     @Override
     public void onApiConnected() {
+        super.onApiConnected();
+
         setupButtonsByFlightState();
         updateFlightModeButtons();
         updateFollowButton();
@@ -278,6 +279,7 @@ public void onApiConnected() {
 
     @Override
     public void onApiDisconnected() {
+        super.onApiDisconnected();
         getBroadcastManager().unregisterReceiver(eventReceiver);
     }
 
@@ -340,11 +342,7 @@ public void onClick(View v) {
                 break;
 
             case R.id.mc_follow: {
-                final FollowState followState = drone.getAttribute(AttributeType.FOLLOW_STATE);
-                if (followState.isEnabled()) {
-                    drone.disableFollowMe();
-                } else
-                    drone.enableFollowMe(FollowType.LEASH);
+                toggleFollowMe();
                 break;
             }
 
diff --git a/Android/src/org/droidplanner/android/fragments/control/RoverFlightControlFragment.java b/Android/src/org/droidplanner/android/fragments/control/RoverFlightControlFragment.java
index 9d8c83ff88..1d63e62a83 100644
--- a/Android/src/org/droidplanner/android/fragments/control/RoverFlightControlFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/control/RoverFlightControlFragment.java
@@ -25,7 +25,7 @@
 /**
  * Created by Fredia Huya-Kouadio on 3/4/15.
  */
-public class RoverFlightControlFragment extends ApiListenerFragment implements FlightControlManagerFragment.SlidingUpHeader, View.OnClickListener {
+public class RoverFlightControlFragment extends BaseFlightControlFragment {
 
     private static final String ACTION_FLIGHT_ACTION_BUTTON = "Rover flight action button";
 
@@ -147,6 +147,7 @@ private void setupButtonsForConnected() {
 
     @Override
     public void onApiConnected() {
+        super.onApiConnected();
         setupButtonsByFlightState();
         updateFlightModeButtons();
         getBroadcastManager().registerReceiver(eventReceiver, intentFilter);
@@ -154,6 +155,7 @@ public void onApiConnected() {
 
     @Override
     public void onApiDisconnected() {
+        super.onApiDisconnected();
         getBroadcastManager().unregisterReceiver(eventReceiver);
     }
 
diff --git a/Android/src/org/droidplanner/android/fragments/helpers/ApiListenerDialogFragment.java b/Android/src/org/droidplanner/android/fragments/helpers/ApiListenerDialogFragment.java
index e8553652bc..37af240b61 100644
--- a/Android/src/org/droidplanner/android/fragments/helpers/ApiListenerDialogFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/helpers/ApiListenerDialogFragment.java
@@ -13,6 +13,7 @@
 import org.droidplanner.android.DroidPlannerApp;
 import org.droidplanner.android.fragments.SettingsFragment;
 import org.droidplanner.android.proxy.mission.MissionProxy;
+import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 import org.droidplanner.android.utils.unit.UnitManager;
 import org.droidplanner.android.utils.unit.providers.area.AreaUnitProvider;
 import org.droidplanner.android.utils.unit.providers.length.LengthUnitProvider;
@@ -73,6 +74,10 @@ protected Context getContext(){
         return dpApp.getApplicationContext();
     }
 
+    protected DroidPlannerPrefs getAppPrefs(){
+        return dpApp.getAppPreferences();
+    }
+
     @Override
     public void onAttach(Activity activity){
         super.onAttach(activity);
diff --git a/Android/src/org/droidplanner/android/fragments/mode/ModeGuidedFragment.java b/Android/src/org/droidplanner/android/fragments/mode/ModeGuidedFragment.java
index 0dcb4d7bb8..b962a17918 100644
--- a/Android/src/org/droidplanner/android/fragments/mode/ModeGuidedFragment.java
+++ b/Android/src/org/droidplanner/android/fragments/mode/ModeGuidedFragment.java
@@ -11,7 +11,6 @@
 import com.o3dr.services.android.lib.coordinate.LatLongAlt;
 import com.o3dr.services.android.lib.drone.attribute.AttributeType;
 import com.o3dr.services.android.lib.drone.property.GuidedState;
-import com.o3dr.services.android.lib.drone.property.State;
 import com.o3dr.services.android.lib.drone.property.Type;
 
 import org.beyene.sius.unit.length.LengthUnit;
@@ -19,29 +18,28 @@
 import org.droidplanner.android.activities.FlightActivity;
 import org.droidplanner.android.fragments.FlightMapFragment;
 import org.droidplanner.android.fragments.helpers.ApiListenerFragment;
+import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 import org.droidplanner.android.utils.unit.providers.length.LengthUnitProvider;
 import org.droidplanner.android.widgets.spinnerWheel.CardWheelHorizontalView;
 import org.droidplanner.android.widgets.spinnerWheel.adapters.LengthWheelAdapter;
 
 public class ModeGuidedFragment extends ApiListenerFragment implements
-        CardWheelHorizontalView.OnCardWheelScrollListener<LengthUnit>,FlightMapFragment.OnGuidedClickListener {
-
-    private static final float DEFAULT_ALTITUDE = 2f;
+        CardWheelHorizontalView.OnCardWheelScrollListener<LengthUnit>, FlightMapFragment.OnGuidedClickListener {
 
     private CardWheelHorizontalView<LengthUnit> mAltitudeWheel;
     protected FlightActivity parentActivity;
 
     @Override
-    public void onAttach(Activity activity){
+    public void onAttach(Activity activity) {
         super.onAttach(activity);
-        if(!(activity instanceof FlightActivity))
+        if (!(activity instanceof FlightActivity))
             throw new IllegalStateException("Parent activity must be an instance of " + FlightActivity.class.getName());
 
         parentActivity = (FlightActivity) activity;
     }
 
     @Override
-    public void onDetach(){
+    public void onDetach() {
         super.onDetach();
         parentActivity = null;
     }
@@ -55,9 +53,12 @@ public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle sa
     public void onViewCreated(View parentView, Bundle savedInstanceState) {
         super.onViewCreated(parentView, savedInstanceState);
 
+        final DroidPlannerPrefs dpPrefs = getAppPrefs();
+
         final LengthUnitProvider lengthUnitProvider = getLengthUnitProvider();
         final LengthWheelAdapter altitudeAdapter = new LengthWheelAdapter(getContext(), R.layout.wheel_text_centered,
-                lengthUnitProvider.boxBaseValueToTarget(2), lengthUnitProvider.boxBaseValueToTarget(200));
+                lengthUnitProvider.boxBaseValueToTarget(dpPrefs.getMinAltitude()),
+                lengthUnitProvider.boxBaseValueToTarget(dpPrefs.getMaxAltitude()));
 
         mAltitudeWheel = (CardWheelHorizontalView<LengthUnit>) parentView.findViewById(R.id.altitude_spinner);
         mAltitudeWheel.setViewAdapter(altitudeAdapter);
@@ -98,23 +99,24 @@ public void onApiConnected() {
         final Drone drone = getDrone();
 
         if (mAltitudeWheel != null) {
+            final int defaultAlt = getAppPrefs().getDefaultAltitude();
+
             GuidedState guidedState = drone.getAttribute(AttributeType.GUIDED_STATE);
             LatLongAlt coordinate = guidedState == null ? null : guidedState.getCoordinate();
 
             final LengthUnit initialValue = getLengthUnitProvider().boxBaseValueToTarget(
                     Math.max(guidedState == null
-                                    ? DEFAULT_ALTITUDE
-                                    : coordinate == null ? DEFAULT_ALTITUDE : coordinate.getAltitude(),
-                            DEFAULT_ALTITUDE));
+                                    ? defaultAlt
+                                    : coordinate == null ? defaultAlt : coordinate.getAltitude(),
+                            defaultAlt));
             mAltitudeWheel.setCurrentValue(initialValue);
         }
 
         parentActivity.setGuidedClickListener(this);
         Type droneType = drone.getAttribute(AttributeType.TYPE);
-        if(droneType.getDroneType() == Type.TYPE_ROVER){
+        if (droneType.getDroneType() == Type.TYPE_ROVER) {
             mAltitudeWheel.setVisibility(View.GONE);
-        }
-        else{
+        } else {
             mAltitudeWheel.setVisibility(View.VISIBLE);
         }
     }
@@ -127,7 +129,7 @@ public void onApiDisconnected() {
     @Override
     public void onGuidedClick(LatLong coord) {
         final Drone drone = getDrone();
-        if(drone != null)
+        if (drone != null)
             drone.sendGuidedPoint(coord, false);
     }
 }
diff --git a/Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java b/Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java
index df3b51f146..13b0c33fdf 100644
--- a/Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java
+++ b/Android/src/org/droidplanner/android/maps/providers/google_map/GoogleMapFragment.java
@@ -24,17 +24,11 @@
 import com.google.android.gms.common.ConnectionResult;
 import com.google.android.gms.common.GooglePlayServicesUtil;
 import com.google.android.gms.common.api.Api;
-import com.google.android.gms.common.api.GoogleApiClient;
-import com.google.android.gms.common.api.PendingResult;
-import com.google.android.gms.common.api.ResultCallback;
-import com.google.android.gms.common.api.Status;
-import com.google.android.gms.location.LocationListener;
+import com.google.android.gms.location.LocationAvailability;
+import com.google.android.gms.location.LocationCallback;
 import com.google.android.gms.location.LocationRequest;
+import com.google.android.gms.location.LocationResult;
 import com.google.android.gms.location.LocationServices;
-import com.google.android.gms.location.LocationSettingsRequest;
-import com.google.android.gms.location.LocationSettingsResult;
-import com.google.android.gms.location.LocationSettingsStates;
-import com.google.android.gms.location.LocationSettingsStatusCodes;
 import com.google.android.gms.maps.CameraUpdate;
 import com.google.android.gms.maps.CameraUpdateFactory;
 import com.google.android.gms.maps.GoogleMap;
@@ -85,7 +79,7 @@
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicReference;
 
-public class GoogleMapFragment extends SupportMapFragment implements DPMap, LocationListener, GoogleApiClientManager.ManagerListener {
+public class GoogleMapFragment extends SupportMapFragment implements DPMap, GoogleApiClientManager.ManagerListener {
 
     private static final String TAG = GoogleMapFragment.class.getSimpleName();
 
@@ -96,13 +90,10 @@ public class GoogleMapFragment extends SupportMapFragment implements DPMap, Loca
     public static final String MAP_TYPE_NORMAL = "Normal";
     public static final String MAP_TYPE_TERRAIN = "Terrain";
 
-    // TODO: update the interval based on the user's current activity.
     private static final long USER_LOCATION_UPDATE_INTERVAL = 30000; // ms
-    private static final long USER_LOCATION_UPDATE_FASTEST_INTERVAL = 1000; // ms
+    private static final long USER_LOCATION_UPDATE_FASTEST_INTERVAL = 5000; // ms
     private static final float USER_LOCATION_UPDATE_MIN_DISPLACEMENT = 0; // m
 
-    public static final int REQUEST_CHECK_SETTINGS = 147;
-
     private static final float GO_TO_MY_LOCATION_ZOOM = 19f;
 
     private static final IntentFilter eventFilter = new IntentFilter();
@@ -110,7 +101,6 @@ public class GoogleMapFragment extends SupportMapFragment implements DPMap, Loca
     static {
         eventFilter.addAction(AttributeEvent.GPS_POSITION);
         eventFilter.addAction(SettingsFragment.ACTION_MAP_ROTATION_PREFERENCE_UPDATED);
-        eventFilter.addAction(SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED);
     }
 
     private final static Api<? extends Api.ApiOptions.NotRequiredOptions>[] apisList = new Api[]{LocationServices.API};
@@ -142,23 +132,6 @@ public void onMapReady(GoogleMap googleMap) {
                         }
                     });
                     break;
-
-                case SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED:
-                    final int resultCode = intent.getIntExtra(SettingsFragment.EXTRA_RESULT_CODE, Activity.RESULT_OK);
-                    switch (resultCode) {
-                        case Activity.RESULT_OK:
-                            // All required changes were successfully made. Try to acquire user location again
-                            mGApiClientMgr.addTask(mRequestLocationUpdateTask);
-                            break;
-
-                        case Activity.RESULT_CANCELED:
-                            // The user was asked to change settings, but chose not to
-                            Toast.makeText(getActivity(), "Please update your location settings!", Toast.LENGTH_LONG).show();
-                            break;
-                        default:
-                            break;
-                    }
-                    break;
             }
         }
     };
@@ -170,6 +143,52 @@ public void onMapReady(GoogleMap googleMap) {
     private final AtomicReference<AutoPanMode> mPanMode = new AtomicReference<AutoPanMode>(
             AutoPanMode.DISABLED);
 
+    private final Handler handler = new Handler();
+
+    private final LocationCallback locationCb = new LocationCallback() {
+        @Override
+        public void onLocationAvailability(LocationAvailability locationAvailability) {
+            super.onLocationAvailability(locationAvailability);
+        }
+
+        @Override
+        public void onLocationResult(LocationResult result) {
+            super.onLocationResult(result);
+
+            final Location location = result.getLastLocation();
+            if (location == null)
+                return;
+
+            //Update the user location icon.
+            if (userMarker == null) {
+                final MarkerOptions options = new MarkerOptions()
+                        .position(new LatLng(location.getLatitude(), location.getLongitude()))
+                        .draggable(false)
+                        .flat(true)
+                        .visible(true)
+                        .icon(BitmapDescriptorFactory.fromResource(R.drawable.blue));
+
+                getMapAsync(new OnMapReadyCallback() {
+                    @Override
+                    public void onMapReady(GoogleMap googleMap) {
+                        userMarker = googleMap.addMarker(options);
+                    }
+                });
+            } else {
+                userMarker.setPosition(new LatLng(location.getLatitude(), location.getLongitude()));
+            }
+
+            if (mPanMode.get() == AutoPanMode.USER) {
+                Log.d(TAG, "User location changed.");
+                updateCamera(DroneHelper.LocationToCoord(location), (int) getMap().getCameraPosition().zoom);
+            }
+
+            if (mLocationListener != null) {
+                mLocationListener.onLocationChanged(location);
+            }
+        }
+    };
+
     private final GoogleApiClientTask mGoToMyLocationTask = new GoogleApiClientTask() {
         @Override
         public void doRun() {
@@ -186,7 +205,7 @@ public void doRun() {
     private final GoogleApiClientTask mRemoveLocationUpdateTask = new GoogleApiClientTask() {
         @Override
         public void doRun() {
-            LocationServices.FusedLocationApi.removeLocationUpdates(getGoogleApiClient(), GoogleMapFragment.this);
+            LocationServices.FusedLocationApi.removeLocationUpdates(getGoogleApiClient(), locationCb);
         }
     };
 
@@ -194,55 +213,13 @@ public void doRun() {
         @Override
         public void doRun() {
             final LocationRequest locationReq = LocationRequest.create()
-                    .setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
+                    .setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)
                     .setFastestInterval(USER_LOCATION_UPDATE_FASTEST_INTERVAL)
                     .setInterval(USER_LOCATION_UPDATE_INTERVAL)
                     .setSmallestDisplacement(USER_LOCATION_UPDATE_MIN_DISPLACEMENT);
 
-            final GoogleApiClient googleApiClient = getGoogleApiClient();
-
-            LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
-                    .addLocationRequest(locationReq);
-
-            PendingResult<LocationSettingsResult> result =
-                    LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
-
-            result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
-                @Override
-                public void onResult(LocationSettingsResult callback) {
-                    final Status status = callback.getStatus();
-
-                    switch (status.getStatusCode()) {
-                        case LocationSettingsStatusCodes.SUCCESS:
-                            // All location settings are satisfied. The client can initialize location
-                            // requests here.
-                            LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationReq,
-                                    GoogleMapFragment.this);
-                            break;
-
-                        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
-                            // Location settings are not satisfied. But could be fixed by showing the user
-                            // a dialog.
-                            try {
-                                // Show the dialog by calling startResolutionForResult(),
-                                // and check the result in onActivityResult().
-                                status.startResolutionForResult(getActivity(), REQUEST_CHECK_SETTINGS);
-                            } catch (IntentSender.SendIntentException e) {
-                                // Ignore the error.
-                                Log.e(TAG, e.getMessage(), e);
-                            }
-                            break;
-
-                        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
-                            // Location settings are not satisfied. However, we have no way to fix the
-                            // settings so we won't show the dialog.
-                            Log.w(TAG, "Unable to get accurate user location.");
-                            Toast.makeText(getActivity(), "Unable to get accurate location. Please update your " +
-                                    "location settings!", Toast.LENGTH_LONG).show();
-                            break;
-                    }
-                }
-            });
+            LocationServices.FusedLocationApi.requestLocationUpdates(getGoogleApiClient(), locationReq,
+                    locationCb, handler.getLooper());
         }
     };
 
@@ -281,6 +258,12 @@ protected void doRun() {
     protected DroidPlannerApp dpApp;
     private Polygon footprintPoly;
 
+    /*
+    Tile overlay
+     */
+    private TileOverlay onlineTileProvider;
+    private TileOverlay offlineTileProvider;
+
     @Override
     public void onAttach(Activity activity) {
         super.onAttach(activity);
@@ -746,17 +729,17 @@ public void zoomToFit(List<LatLong> coords) {
                 @Override
                 public void onMapReady(GoogleMap googleMap) {
                     final Activity activity = getActivity();
-                    if(activity == null)
+                    if (activity == null)
                         return;
 
-                    final View rootView = ((ViewGroup)activity.findViewById(android.R.id.content)).getChildAt(0);
-                    if(rootView == null)
+                    final View rootView = ((ViewGroup) activity.findViewById(android.R.id.content)).getChildAt(0);
+                    if (rootView == null)
                         return;
 
                     final int height = rootView.getHeight();
                     final int width = rootView.getWidth();
                     Log.d(TAG, String.format(Locale.US, "Screen W %d, H %d", width, height));
-                    if(height > 0 && width > 0) {
+                    if (height > 0 && width > 0) {
                         CameraUpdate animation = CameraUpdateFactory.newLatLngBounds(bounds, width, height, 100);
                         googleMap.animateCamera(animation);
                     }
@@ -865,7 +848,7 @@ public boolean onMarkerClick(Marker marker) {
 
                 if (mMarkerClickListener != null) {
                     final MarkerInfo markerInfo = mBiMarkersMap.getKey(marker);
-                    if(markerInfo != null)
+                    if (markerInfo != null)
                         return mMarkerClickListener.onMarkerClick(markerInfo);
                 }
                 return false;
@@ -950,37 +933,6 @@ public double getMapRotation() {
         }
     }
 
-    @Override
-    public void onLocationChanged(Location location) {
-        //Update the user location icon.
-        if (userMarker == null) {
-            final MarkerOptions options = new MarkerOptions()
-                    .position(new LatLng(location.getLatitude(), location.getLongitude()))
-                    .draggable(false)
-                    .flat(true)
-                    .visible(true)
-                    .icon(BitmapDescriptorFactory.fromResource(R.drawable.blue));
-
-            getMapAsync(new OnMapReadyCallback() {
-                @Override
-                public void onMapReady(GoogleMap googleMap) {
-                    userMarker = googleMap.addMarker(options);
-                }
-            });
-        } else {
-            userMarker.setPosition(new LatLng(location.getLatitude(), location.getLongitude()));
-        }
-
-        if (mPanMode.get() == AutoPanMode.USER) {
-            Log.d(TAG, "User location changed.");
-            updateCamera(DroneHelper.LocationToCoord(location), (int) getMap().getCameraPosition().zoom);
-        }
-
-        if (mLocationListener != null) {
-            mLocationListener.onLocationChanged(location);
-        }
-    }
-
     @Override
     public void skipMarkerClickEvents(boolean skip) {
         useMarkerClickAsMapClick = skip;
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxTileProvider.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxTileProvider.java
new file mode 100644
index 0000000000..ef468d0d39
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxTileProvider.java
@@ -0,0 +1,42 @@
+package org.droidplanner.android.maps.providers.mapbox;
+
+import android.util.Log;
+
+import com.google.android.gms.maps.model.UrlTileProvider;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/11/15.
+ */
+public class MapboxTileProvider extends UrlTileProvider {
+
+    private final static String TAG = MapboxTileProvider.class.getSimpleName();
+
+    private final String mapboxId;
+    private final String mapboxAccessToken;
+    private final int maxZoomLevel;
+
+    public MapboxTileProvider(String mapboxId, String mapboxAccessToken, int maxZoomLevel) {
+        super(MapboxUtils.TILE_WIDTH, MapboxUtils.TILE_HEIGHT);
+        this.mapboxId = mapboxId;
+        this.mapboxAccessToken = mapboxAccessToken;
+        this.maxZoomLevel = maxZoomLevel;
+    }
+
+    @Override
+    public URL getTileUrl(int x, int y, int zoom) {
+        if (zoom <= maxZoomLevel) {
+            final String tileUrl = MapboxUtils.getMapTileURL(mapboxId, mapboxAccessToken, zoom, x, y);
+            try {
+                return new URL(tileUrl);
+            } catch (MalformedURLException e) {
+                Log.e(TAG, "Error while building url for mapbox map tile.", e);
+            }
+        }
+        return null;
+    }
+
+
+}
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxUtils.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxUtils.java
new file mode 100644
index 0000000000..da8c44bc70
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/MapboxUtils.java
@@ -0,0 +1,61 @@
+package org.droidplanner.android.maps.providers.mapbox;
+
+import android.text.TextUtils;
+
+import java.util.Locale;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/11/15.
+ */
+public class MapboxUtils {
+
+    //Private constructor to prevent instantiation.
+    private MapboxUtils(){}
+
+    public static final int TILE_WIDTH = 512; //pixels
+    public static final int TILE_HEIGHT = 512; //pixels
+
+    public static final String MAPBOX_BASE_URL_V4 = "https://a.tiles.mapbox.com/v4/";
+
+    public static String getMapTileURL(String mapID, String accessToken, int zoom, int x, int y) {
+        return String.format(Locale.US, "https://a.tiles.mapbox.com/v4/%s/%d/%d/%d%s.%s?access_token=%s",
+                mapID, zoom, x, y, "@2x", "png", accessToken);
+    }
+
+    public static String markerIconURL(String accessToken, String size, String symbol, String color) {
+        // Make a string which follows the Mapbox Core API spec for stand-alone markers. This relies on the Mapbox API
+        // for error checking.
+
+        StringBuffer marker = new StringBuffer("pin-");
+        final String lowerCaseSize = size.toLowerCase(Locale.US);
+
+        if (lowerCaseSize.charAt(0) == 'l') {
+            marker.append("l"); // large
+        } else if (lowerCaseSize.charAt(0) == 's') {
+            marker.append("s"); // small
+        } else {
+            marker.append("m"); // default to medium
+        }
+
+        if (!TextUtils.isEmpty(symbol)) {
+            marker.append(String.format("-%s+", symbol));
+        } else {
+            marker.append("+");
+        }
+
+        marker.append(color.replaceAll("#", ""));
+
+//        if (AppUtils.isRunningOn2xOrGreaterScreen(context)) {
+//            marker.append("@2x");
+//        }
+        marker.append(".png");
+
+        marker.append("?access_token=");
+        marker.append(accessToken);
+        return String.format(Locale.US, MAPBOX_BASE_URL_V4 + "marker/%s", marker);
+    }
+
+    public static String getUserAgent() {
+        return "Mapbox Android SDK/0.7.3";
+    }
+}
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/OfflineTileProvider.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/OfflineTileProvider.java
new file mode 100644
index 0000000000..f6a4d733c6
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/OfflineTileProvider.java
@@ -0,0 +1,42 @@
+package org.droidplanner.android.maps.providers.mapbox;
+
+import android.content.Context;
+
+import com.google.android.gms.maps.model.Tile;
+import com.google.android.gms.maps.model.TileProvider;
+
+import org.droidplanner.android.data.DatabaseState;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/11/15.
+ */
+public class OfflineTileProvider implements TileProvider {
+
+    private static final String TAG = OfflineTileProvider.class.getSimpleName();
+
+    private final Context context;
+    private final String mapboxId;
+    private final String mapboxAccessToken;
+    private final int maxZoomLevel;
+
+    public OfflineTileProvider(Context context, String mapboxId, String mapboxAccessToken, int maxZoomLevel) {
+        this.context = context;
+        this.mapboxId = mapboxId;
+        this.mapboxAccessToken = mapboxAccessToken;
+        this.maxZoomLevel = maxZoomLevel;
+    }
+
+    @Override
+    public Tile getTile(int x, int y, int zoom) {
+        if (zoom > maxZoomLevel) {
+            return TileProvider.NO_TILE;
+        }
+
+        final String tileUri = MapboxUtils.getMapTileURL(mapboxId, mapboxAccessToken, zoom, x, y);
+        byte[] data = DatabaseState.getOfflineDatabaseHandlerForMapId(context, mapboxId).dataForURL(tileUri);
+        if (data == null || data.length == 0)
+            return TileProvider.NO_TILE;
+
+        return new Tile(MapboxUtils.TILE_WIDTH, MapboxUtils.TILE_HEIGHT, data);
+    }
+}
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloader.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloader.java
new file mode 100644
index 0000000000..a2a379e5bd
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloader.java
@@ -0,0 +1,548 @@
+package org.droidplanner.android.maps.providers.mapbox.offline;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.text.TextUtils;
+import android.util.Log;
+
+import com.google.android.gms.maps.model.VisibleRegion;
+
+import org.droidplanner.android.data.DatabaseState;
+import org.droidplanner.android.maps.providers.mapbox.MapboxUtils;
+import org.droidplanner.android.utils.NetworkUtils;
+import org.droidplanner.android.utils.Utils;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.BufferedReader;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class MapDownloader {
+
+    private static final String TAG = MapDownloader.class.getSimpleName();
+
+    /**
+     * The possible states of the offline map downloader.
+     */
+    public enum MBXOfflineMapDownloaderState {
+        /**
+         * An offline map download job is in progress.
+         */
+        MBXOfflineMapDownloaderStateRunning,
+        /**
+         * An offline map download job is being canceled.
+         */
+        MBXOfflineMapDownloaderStateCanceling,
+        /**
+         * The offline map downloader is ready to begin a new offline map download job.
+         */
+        MBXOfflineMapDownloaderStateAvailable
+    }
+
+    private MBXOfflineMapDownloaderState state;
+    private final AtomicInteger totalFilesWritten = new AtomicInteger(0);
+    private final AtomicInteger totalFilesExpectedToWrite = new AtomicInteger(0);
+
+    private final Context context;
+    private ExecutorService downloadsScheduler;
+    private final ArrayList<MapDownloaderListener> listeners = new ArrayList<>();
+
+    public MapDownloader(Context context) {
+        this.context = context;
+        setupDownloadScheduler();
+
+        this.state = MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateAvailable;
+    }
+
+    public MBXOfflineMapDownloaderState getState() {
+        return state;
+    }
+
+    public boolean addMapDownloaderListener(MapDownloaderListener listener) {
+        return listeners.add(listener);
+    }
+
+    public boolean removeMapDownloaderListener(MapDownloaderListener listener) {
+        return listeners.remove(listener);
+    }
+
+    public void cancelDownload() {
+        if (state == MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateRunning) {
+            this.state = MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateCanceling;
+            notifyDelegateOfStateChange();
+        }
+
+        setupDownloadScheduler();
+
+        if (state == MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateCanceling) {
+            this.state = MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateAvailable;
+            notifyDelegateOfStateChange();
+        }
+    }
+
+    private void setupDownloadScheduler() {
+        if (downloadsScheduler != null) {
+            downloadsScheduler.shutdownNow();
+        }
+
+        final int processorsCount = (int) (Runtime.getRuntime().availableProcessors() * 1.5f);
+        Log.v(TAG, "Using " + processorsCount + " processors.");
+        downloadsScheduler = Executors.newFixedThreadPool(processorsCount);
+    }
+
+/*
+    Delegate Notifications
+*/
+
+    public void notifyDelegateOfStateChange() {
+        for (MapDownloaderListener listener : listeners) {
+            listener.stateChanged(this.state);
+        }
+    }
+
+    public void notifyDelegateOfInitialCount(int totalFilesExpectedToWrite) {
+        for (MapDownloaderListener listener : listeners) {
+            listener.initialCountOfFiles(totalFilesExpectedToWrite);
+        }
+    }
+
+    public void notifyDelegateOfProgress(int totalFilesWritten, int totalFilesExpectedToWrite) {
+        for (MapDownloaderListener listener : listeners) {
+            listener.progressUpdate(totalFilesWritten, totalFilesExpectedToWrite);
+        }
+    }
+
+    public void notifyDelegateOfNetworkConnectivityError(Throwable error) {
+        for (MapDownloaderListener listener : listeners) {
+            listener.networkConnectivityError(error);
+        }
+    }
+
+    public void notifyDelegateOfSqliteError(Throwable error) {
+        for (MapDownloaderListener listener : listeners) {
+            listener.sqlLiteError(error);
+        }
+    }
+
+    public void notifyDelegateOfHTTPStatusError(int status, String url) {
+        for (MapDownloaderListener listener : listeners) {
+            listener.httpStatusError(new Exception(String.format(Locale.US, "HTTP Status Error %d, for url = %s", status,
+                    url)));
+        }
+    }
+
+    public void notifyDelegateOfCompletionWithOfflineMapDatabase() {
+        for (MapDownloaderListener listener : listeners) {
+            listener.completionOfOfflineDatabaseMap();
+        }
+    }
+
+    public void startDownloading(final String mapId) {
+
+        // Get the actual URLs
+        ArrayList<String> urls = sqliteReadArrayOfOfflineMapURLsToBeDownloadLimit(mapId, -1);
+        this.totalFilesExpectedToWrite.set(urls.size());
+        this.totalFilesWritten.set(0);
+
+        notifyDelegateOfInitialCount(totalFilesExpectedToWrite.get());
+
+        Log.d(TAG, String.format(Locale.US, "number of urls to download = %d", urls.size()));
+        if (this.totalFilesExpectedToWrite.get() == 0) {
+            finishUpDownloadProcess();
+            return;
+        }
+
+        if (!NetworkUtils.isNetworkAvailable(context)) {
+            Log.e(TAG, "Network is not available.");
+            notifyDelegateOfNetworkConnectivityError(new IllegalStateException("Network is not available"));
+            return;
+        }
+
+        final CountDownLatch downloadsTracker = new CountDownLatch(this.totalFilesExpectedToWrite.get());
+        for (final String url : urls) {
+            downloadsScheduler.execute(new Runnable() {
+                @Override
+                public void run() {
+                    HttpURLConnection conn = null;
+                    try {
+                        conn = NetworkUtils.getHttpURLConnection(new URL(url));
+                        Log.d(TAG, "URL to download = " + conn.getURL().toString());
+                        conn.setConnectTimeout(60000);
+                        conn.connect();
+                        int rc = conn.getResponseCode();
+                        if (rc != HttpURLConnection.HTTP_OK) {
+                            String msg = String.format(Locale.US, "HTTP Error connection.  Response Code = %d for url = %s", rc, conn.getURL().toString());
+                            Log.w(TAG, msg);
+                            notifyDelegateOfHTTPStatusError(rc, url);
+                            throw new IOException(msg);
+                        }
+
+                        ByteArrayOutputStream bais = new ByteArrayOutputStream();
+                        InputStream is = null;
+                        try {
+                            is = conn.getInputStream();
+                            // Read 4K at a time
+                            byte[] byteChunk = new byte[4096];
+                            int n;
+
+                            while ((n = is.read(byteChunk)) > 0) {
+                                bais.write(byteChunk, 0, n);
+                            }
+                        } catch (IOException e) {
+                            Log.e(TAG, String.format(Locale.US, "Failed while reading bytes from %s: %s", conn.getURL().toString(), e.getMessage()));
+                            e.printStackTrace();
+                        } finally {
+                            if (is != null) {
+                                is.close();
+                            }
+                            conn.disconnect();
+                        }
+                        sqliteSaveDownloadedData(mapId, bais.toByteArray(), url);
+                    } catch (IOException e) {
+                        Log.e(TAG, "Error occurred while retrieving map data.", e);
+                    } finally {
+                        downloadsTracker.countDown();
+
+                        if (conn != null) {
+                            conn.disconnect();
+                        }
+                    }
+
+                }
+            });
+        }
+
+        downloadsScheduler.execute(new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    downloadsTracker.await();
+                } catch (InterruptedException e) {
+                    Log.e(TAG, "Error while waiting for downloads to complete.", e);
+                } finally {
+                    finishUpDownloadProcess();
+                }
+            }
+        });
+    }
+
+/*
+    Implementation: sqlite stuff
+*/
+
+    public void sqliteSaveDownloadedData(String mapId, byte[] data, String url) {
+        if (Utils.runningOnMainThread()) {
+            Log.w(TAG, "trying to run sqliteSaveDownloadedData() on main thread. Return.");
+            return;
+        }
+
+        // Bail out if the state has changed to canceling, suspended, or available
+        if (this.state != MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateRunning) {
+            Log.w(TAG, "sqliteSaveDownloadedData() is not in a Running state so bailing.  State = " + this.state);
+            return;
+        }
+
+        // Open the database read-write and multi-threaded. The slightly obscure c-style variable names here and below are
+        // used to stay consistent with the sqlite documentaion.
+        // Continue by inserting an image blob into the data table
+        SQLiteDatabase db = DatabaseState.getOfflineDatabaseHandlerForMapId(context, mapId)
+                .getWritableDatabase();
+        try {
+            db.beginTransaction();
+
+            ContentValues values = new ContentValues();
+            values.put(OfflineDatabaseHandler.FIELD_DATA_VALUE, data);
+            db.insert(OfflineDatabaseHandler.TABLE_DATA, null, values);
+
+            db.execSQL(String.format(Locale.US, "UPDATE %s SET %s=200, %s=last_insert_rowid() WHERE %s='%s';", OfflineDatabaseHandler.TABLE_RESOURCES, OfflineDatabaseHandler.FIELD_RESOURCES_STATUS, OfflineDatabaseHandler.FIELD_RESOURCES_ID, OfflineDatabaseHandler.FIELD_RESOURCES_URL, url));
+            db.setTransactionSuccessful();
+            db.endTransaction();
+//        db.close();
+        }catch(IllegalStateException e){
+            Log.e(TAG, "Error while saving downloader data to the database.", e);
+        }
+
+        // Update the progress
+        notifyDelegateOfProgress(this.totalFilesWritten.incrementAndGet(), this.totalFilesExpectedToWrite.get());
+        Log.d(TAG, "totalFilesWritten = " + this.totalFilesWritten + "; totalFilesExpectedToWrite = " + this
+                .totalFilesExpectedToWrite.get());
+    }
+
+    private void finishUpDownloadProcess() {
+        if (this.state == MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateRunning) {
+            Log.i(TAG, "Just finished downloading all materials.  Persist the OfflineMapDatabase, change the state, and call it a day.");
+            // This is what to do when we've downloaded all the files
+            notifyDelegateOfCompletionWithOfflineMapDatabase();
+            this.state = MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateAvailable;
+            notifyDelegateOfStateChange();
+        }
+    }
+
+    public ArrayList<String> sqliteReadArrayOfOfflineMapURLsToBeDownloadLimit(String mapId, int limit) {
+        ArrayList<String> results = new ArrayList<String>();
+        if (Utils.runningOnMainThread()) {
+            Log.w(TAG, "Attempting to run sqliteReadArrayOfOfflineMapURLsToBeDownloadLimit() on main thread.  Returning.");
+            return results;
+        }
+
+        // Read up to limit undownloaded urls from the offline map database
+        String query = String.format(Locale.US, "SELECT %s FROM %s WHERE %s IS NULL", OfflineDatabaseHandler.FIELD_RESOURCES_URL, OfflineDatabaseHandler.TABLE_RESOURCES, OfflineDatabaseHandler.FIELD_RESOURCES_STATUS);
+        if (limit > 0) {
+            query = query + String.format(Locale.US, " LIMIT %d", limit);
+        }
+        query = query + ";";
+
+        // Open the database
+        SQLiteDatabase db = DatabaseState.getOfflineDatabaseHandlerForMapId(context, mapId)
+                .getReadableDatabase();
+        Cursor cursor = db.rawQuery(query, null);
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
+                do {
+                    results.add(cursor.getString(0));
+                } while (cursor.moveToNext());
+            }
+            cursor.close();
+        }
+//        db.close();
+
+        return results;
+    }
+
+
+    public boolean sqliteCreateDatabaseUsingMetadata(String mapId, List<String> urlStrings) {
+        if (Utils.runningOnMainThread()) {
+            Log.w(TAG, "sqliteCreateDatabaseUsingMetadata() running on main thread.  Returning.");
+            return false;
+        }
+
+        // Build a query to populate the database (map metadata and list of map resource urls)
+        SQLiteDatabase db = DatabaseState.getOfflineDatabaseHandlerForMapId(context, mapId)
+                .getWritableDatabase();
+        db.beginTransaction();
+
+        for (String url : urlStrings) {
+            ContentValues cv = new ContentValues();
+            cv.put(OfflineDatabaseHandler.FIELD_RESOURCES_URL, url);
+            db.insertWithOnConflict(OfflineDatabaseHandler.TABLE_RESOURCES, null, cv, SQLiteDatabase.CONFLICT_IGNORE);
+        }
+
+        db.setTransactionSuccessful();
+        db.endTransaction();
+//        db.close();
+
+        return true;
+    }
+
+/*
+    API: Begin an offline map download
+*/
+
+    public void beginDownloadingMapID(final String mapId, final String accessToken, VisibleRegion mapRegion, int
+            minimumZ, int maximumZ) {
+        beginDownloadingMapID(mapId, accessToken, mapRegion, minimumZ, maximumZ, true, true);
+    }
+
+    public void beginDownloadingMapID(final String mapId, final String accessToken, VisibleRegion mapRegion, int minimumZ, int maximumZ, boolean includeMetadata,
+                                      boolean includeMarkers) {
+        if (state != MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateAvailable) {
+            Log.w(TAG, "state doesn't equal MBXOfflineMapDownloaderStateAvailable so return.  state = " + state);
+            return;
+        }
+
+        // Start a download job to retrieve all the resources needed for using the specified map offline
+        this.state = MBXOfflineMapDownloaderState.MBXOfflineMapDownloaderStateRunning;
+
+        final ArrayList<String> urls = new ArrayList<String>();
+        String dataName = "features.json";    // Only using API V4 for now
+
+        // Include URLs for the metadata and markers json if applicable
+        if (includeMetadata) {
+            urls.add(String.format(Locale.US, MapboxUtils.MAPBOX_BASE_URL_V4 + "%s.json?secure&access_token=%s",
+                    mapId, accessToken));
+        }
+        if (includeMarkers) {
+            urls.add(String.format(Locale.US, MapboxUtils.MAPBOX_BASE_URL_V4 + "%s/%s?access_token=%s", mapId,
+                    dataName, accessToken));
+        }
+
+        // Loop through the zoom levels and lat/lon bounds to generate a list of urls which should be included in the offline map
+        //
+        double minLat = Math.min(
+                Math.min(mapRegion.farLeft.latitude, mapRegion.nearLeft.latitude),
+                Math.min(mapRegion.farRight.latitude, mapRegion.nearRight.latitude));
+        double maxLat = Math.max(
+                Math.max(mapRegion.farLeft.latitude, mapRegion.nearLeft.latitude),
+                Math.max(mapRegion.farRight.latitude, mapRegion.nearRight.latitude));
+
+        double minLon = Math.min(
+                Math.min(mapRegion.farLeft.longitude, mapRegion.nearLeft.longitude),
+                Math.min(mapRegion.farRight.longitude, mapRegion.nearRight.longitude));
+        double maxLon = Math.max(
+                Math.max(mapRegion.farLeft.longitude, mapRegion.nearLeft.longitude),
+                Math.max(mapRegion.farRight.longitude, mapRegion.nearRight.longitude));
+
+        int minX;
+        int maxX;
+        int minY;
+        int maxY;
+        int tilesPerSide;
+
+        Log.d(TAG, "Generating urls for tiles from zoom " + minimumZ + " to zoom " + maximumZ);
+
+        for (int zoom = minimumZ; zoom <= maximumZ; zoom++) {
+            tilesPerSide = Double.valueOf(Math.pow(2.0, zoom)).intValue();
+            minX = Double.valueOf(Math.floor(((minLon + 180.0) / 360.0) * tilesPerSide)).intValue();
+            maxX = Double.valueOf(Math.floor(((maxLon + 180.0) / 360.0) * tilesPerSide)).intValue();
+            minY = Double.valueOf(Math.floor((1.0 - (Math.log(Math.tan(maxLat * Math.PI / 180.0) + 1.0 / Math.cos(maxLat * Math.PI / 180.0)) / Math.PI)) / 2.0 * tilesPerSide)).intValue();
+            maxY = Double.valueOf(Math.floor((1.0 - (Math.log(Math.tan(minLat * Math.PI / 180.0) + 1.0 / Math.cos(minLat * Math.PI / 180.0)) / Math.PI)) / 2.0 * tilesPerSide)).intValue();
+            for (int x = minX; x <= maxX; x++) {
+                for (int y = minY; y <= maxY; y++) {
+                    urls.add(MapboxUtils.getMapTileURL(mapId, accessToken, zoom, x, y));
+                }
+            }
+        }
+
+        Log.d(TAG, urls.size() + " urls generated.");
+
+        // Determine if we need to add marker icon urls (i.e. parse markers.geojson/features.json), and if so, add them
+        if (includeMarkers) {
+            String dName = "markers.geojson";
+            final String geojson = String.format(Locale.US, MapboxUtils.MAPBOX_BASE_URL_V4 + "%s/%s?access_token=%s",
+                    mapId, dName, accessToken);
+
+            if (!NetworkUtils.isNetworkAvailable(context)) {
+                // We got a session level error which probably indicates a connectivity problem such as airplane mode.
+                // Since we must fetch and parse markers.geojson/features.json in order to determine which marker icons need to be
+                // added to the list of urls to download, the lack of network connectivity is a non-recoverable error
+                // here.
+                notifyDelegateOfNetworkConnectivityError(new IllegalStateException("Network is unavailable"));
+                Log.e(TAG, "Network is unavailable.");
+                return;
+            }
+
+            downloadsScheduler.execute(new Runnable() {
+                @Override
+                public void run() {
+                    try {
+                        HttpURLConnection conn = NetworkUtils.getHttpURLConnection(new URL(geojson));
+                        conn.setConnectTimeout(60000);
+                        conn.connect();
+                        if (conn.getResponseCode() != HttpURLConnection.HTTP_OK) {
+                            throw new IOException();
+                        }
+
+                        BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream(), Charset.forName("UTF-8")));
+                        String jsonText = Utils.readAll(rd);
+
+                        // The marker geojson was successfully retrieved, so parse it for marker icons. Note that we shouldn't
+                        // try to save it here, because it may already be in the download queue and saving it twice will mess
+                        // up the count of urls to be downloaded!
+                        //
+                        Set<String> markerIconURLStrings = new HashSet<String>();
+                        markerIconURLStrings.addAll(parseMarkerIconURLStringsFromGeojsonData(accessToken, jsonText));
+                        Log.i(TAG, "Number of markerIconURLs = " + markerIconURLStrings.size());
+                        if (markerIconURLStrings.size() > 0) {
+                            urls.addAll(markerIconURLStrings);
+                        }
+                    } catch (IOException e) {
+                        // The url for markers.geojson/features.json didn't work (some maps don't have any markers). Notify the delegate of the
+                        // problem, and stop attempting to add marker icons, but don't bail out on whole the offline map download.
+                        // The delegate can decide for itself whether it wants to continue or cancel.
+                        //
+                        // TODO
+                        e.printStackTrace();
+/*
+                        [self notifyDelegateOfHTTPStatusError:((NSHTTPURLResponse *)response).statusCode url:response.URL];
+*/
+                    } finally {
+                        startDownloadProcess(mapId, urls);
+                    }
+                }
+            });
+        } else {
+            Log.i(TAG, "No marker icons to worry about, so just start downloading.");
+            // There aren't any marker icons to worry about, so just create database and start downloading
+            startDownloadProcess(mapId, urls);
+        }
+    }
+
+    /**
+     * Private method for Starting the Whole Download Process
+     *
+     * @param urls Map urls
+     */
+    private void startDownloadProcess(final String mapId, final List<String> urls) {
+        downloadsScheduler.execute(new Runnable() {
+            @Override
+            public void run() {
+                // Do database creation / io on background thread
+                if (!sqliteCreateDatabaseUsingMetadata(mapId, urls)) {
+                    Log.e(TAG, "Map Database wasn't created");
+                    return;
+                }
+
+                startDownloading(mapId);
+            }
+        });
+    }
+
+
+    public Set<String> parseMarkerIconURLStringsFromGeojsonData(String accessToken, String data) {
+        HashSet<String> iconURLStrings = new HashSet<String>();
+
+        JSONObject simplestyleJSONDictionary;
+        try {
+            simplestyleJSONDictionary = new JSONObject(data);
+
+            // Find point features in the markers dictionary (if there are any) and add them to the map.
+            JSONArray markers = simplestyleJSONDictionary.getJSONArray("features");
+
+            if (markers != null && markers.length() > 0) {
+                for (int lc = 0; lc < markers.length(); lc++) {
+                    JSONObject feature = markers.optJSONObject(lc);
+                    if (feature != null) {
+                        String type = feature.getJSONObject("geometry").getString("type");
+
+                        if ("Point".equals(type)) {
+                            String size = feature.getJSONObject("properties").getString("marker-size");
+                            String color = feature.getJSONObject("properties").getString("marker-color");
+                            String symbol = feature.getJSONObject("properties").getString("marker-symbol");
+                            if (!TextUtils.isEmpty(size) && !TextUtils.isEmpty(color) && !TextUtils.isEmpty(symbol)) {
+                                String markerURL = MapboxUtils.markerIconURL(accessToken, size, symbol, color);
+                                if (!TextUtils.isEmpty(markerURL)) {
+                                    iconURLStrings.add(markerURL);
+                                }
+                            }
+                        }
+                    }
+                    // This is the last line of the loop
+                }
+            }
+        } catch (JSONException e) {
+            Log.e(TAG, e.getMessage(), e);
+        }
+
+        // Return only the unique icon urls
+        return iconURLStrings;
+    }
+
+}
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloaderListener.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloaderListener.java
new file mode 100644
index 0000000000..7d8b5f11ab
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/MapDownloaderListener.java
@@ -0,0 +1,13 @@
+package org.droidplanner.android.maps.providers.mapbox.offline;
+
+public interface MapDownloaderListener {
+
+    public void stateChanged(MapDownloader.MBXOfflineMapDownloaderState newState);
+    public void initialCountOfFiles(int numberOfFiles);
+    public void progressUpdate(int numberOfFilesWritten, int numberOfFilesExcepted);
+    public void networkConnectivityError(Throwable error);
+    public void sqlLiteError(Throwable error);
+    public void httpStatusError(Throwable error);
+    public void completionOfOfflineDatabaseMap();
+
+}
diff --git a/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/OfflineDatabaseHandler.java b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/OfflineDatabaseHandler.java
new file mode 100644
index 0000000000..e45ea1542a
--- /dev/null
+++ b/Android/src/org/droidplanner/android/maps/providers/mapbox/offline/OfflineDatabaseHandler.java
@@ -0,0 +1,94 @@
+package org.droidplanner.android.maps.providers.mapbox.offline;
+
+import android.content.Context;
+import android.database.Cursor;
+import android.database.SQLException;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.util.Log;
+
+public class OfflineDatabaseHandler extends SQLiteOpenHelper {
+
+    private static final String TAG = OfflineDatabaseHandler.class.getSimpleName();
+
+    // All Static variables
+    // Database Version
+    public static final int DATABASE_VERSION = 1;
+
+    // Table name(s)
+    public static final String TABLE_DATA = "data";
+    public static final String TABLE_RESOURCES = "resources";
+
+    // Table Fields
+    public static final String FIELD_DATA_ID = "id";
+    public static final String FIELD_DATA_VALUE = "value";
+
+    public static final String FIELD_RESOURCES_ID = "id";
+    public static final String FIELD_RESOURCES_URL = "url";
+    public static final String FIELD_RESOURCES_STATUS = "status";
+
+    /**
+     * Constructor
+     *
+     * @param context Context
+     */
+    public OfflineDatabaseHandler(Context context, String dbName) {
+        super(context, dbName, null, DATABASE_VERSION);
+    }
+
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+        Log.i(TAG, "onCreate() called... Setting up application's database.");
+        // Create The table(s)
+        String data = "CREATE TABLE " + TABLE_DATA + " (" + FIELD_DATA_ID + " INTEGER PRIMARY KEY, " + FIELD_DATA_VALUE + " BLOB);";
+        String resources = "CREATE TABLE " + TABLE_RESOURCES + " (" + FIELD_RESOURCES_URL + " TEXT UNIQUE, " + FIELD_RESOURCES_STATUS + " TEXT, " + FIELD_RESOURCES_ID + " INTEGER REFERENCES data);";
+
+        db.execSQL("PRAGMA foreign_keys=ON;");
+        db.beginTransaction();
+
+        try {
+            db.execSQL(data);
+            db.execSQL(resources);
+            db.setTransactionSuccessful();
+        } catch (SQLException e) {
+            Log.e(TAG, "Error creating databases", e);
+        } finally {
+            db.endTransaction();
+        }
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data");
+        db.execSQL("PRAGMA foreign_keys=OFF;");
+        db.execSQL("drop table if exists " + TABLE_DATA);
+        db.execSQL("drop table if exists " + TABLE_RESOURCES);
+        onCreate(db);
+    }
+
+    public byte[] dataForURL(String url) {
+        return sqliteDataForURL(url);
+    }
+
+    public byte[] sqliteDataForURL(String url) {
+        SQLiteDatabase db = getReadableDatabase();
+
+        String query = "SELECT " + OfflineDatabaseHandler.FIELD_DATA_VALUE + " FROM " + OfflineDatabaseHandler.TABLE_DATA +
+                " WHERE " + OfflineDatabaseHandler.FIELD_DATA_ID +
+                "= (SELECT " + OfflineDatabaseHandler.FIELD_RESOURCES_ID + " from " +
+                OfflineDatabaseHandler.TABLE_RESOURCES + " where " + OfflineDatabaseHandler.FIELD_RESOURCES_URL +
+                " = '" + url + "');";
+
+        Cursor cursor = db.rawQuery(query, null);
+
+        byte[] blob = null;
+        if (cursor != null) {
+            if (cursor.moveToFirst()) {
+                blob = cursor.getBlob(cursor.getColumnIndex(OfflineDatabaseHandler.FIELD_DATA_VALUE));
+            }
+            cursor.close();
+        }
+//        db.close();
+        return blob;
+    }
+}
diff --git a/Android/src/org/droidplanner/android/notifications/TTSNotificationProvider.java b/Android/src/org/droidplanner/android/notifications/TTSNotificationProvider.java
index 39d0ecb660..87f1436749 100644
--- a/Android/src/org/droidplanner/android/notifications/TTSNotificationProvider.java
+++ b/Android/src/org/droidplanner/android/notifications/TTSNotificationProvider.java
@@ -1,5 +1,6 @@
 package org.droidplanner.android.notifications;
 
+import android.annotation.SuppressLint;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
@@ -31,8 +32,11 @@
 import org.droidplanner.android.fragments.SettingsFragment;
 import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Locale;
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 /**
@@ -138,7 +142,10 @@ public void onReceive(Context context, Intent intent) {
                     break;
                 case AttributeEvent.MISSION_ITEM_UPDATED:
                     int currentWaypoint = intent.getIntExtra(AttributeEventExtra.EXTRA_MISSION_CURRENT_WAYPOINT, 0);
-                    speak("Going for waypoint " + currentWaypoint);
+					if(currentWaypoint != 0) {
+						//Zeroth waypoint is the home location.
+						speak("Going for waypoint " + currentWaypoint);
+					}
                     break;
                 case AttributeEvent.FOLLOW_START:
                     speak("Following");
@@ -292,19 +299,34 @@ private void scheduleWatchdog() {
 		}
 	}
 
+	@SuppressLint("NewApi")
 	@Override
 	public void onInit(int status) {
 		if (status == TextToSpeech.SUCCESS) {
 			// TODO: check if the language is available
 			Locale ttsLanguage;
-			if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
+			final int sdkVersion = Build.VERSION.SDK_INT;
+			if (sdkVersion >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
 				ttsLanguage = tts.getDefaultLanguage();
 			} else {
 				ttsLanguage = tts.getLanguage();
 			}
 
-			if (ttsLanguage == null) {
-				ttsLanguage = Locale.US;
+			if (ttsLanguage == null || tts.isLanguageAvailable(ttsLanguage) == TextToSpeech.LANG_NOT_SUPPORTED) {
+				final List<Locale> availableLanguages = new ArrayList<>(tts.getAvailableLanguages());
+
+				if(!availableLanguages.isEmpty()) {
+					//Pick the first available language.
+					ttsLanguage = availableLanguages.get(0);
+				}
+				else {
+					ttsLanguage = Locale.US;
+				}
+			}
+
+			if(tts.isLanguageAvailable(ttsLanguage) == TextToSpeech.LANG_MISSING_DATA){
+				context.startActivity(new Intent(TextToSpeech.Engine.ACTION_INSTALL_TTS_DATA)
+						.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK));
 			}
 
 			int supportStatus = tts.setLanguage(ttsLanguage);
diff --git a/Android/src/org/droidplanner/android/proxy/mission/MissionProxy.java b/Android/src/org/droidplanner/android/proxy/mission/MissionProxy.java
index 4a752f25b5..d8a42df00e 100644
--- a/Android/src/org/droidplanner/android/proxy/mission/MissionProxy.java
+++ b/Android/src/org/droidplanner/android/proxy/mission/MissionProxy.java
@@ -37,6 +37,7 @@
 import org.droidplanner.android.utils.collection.CircularQueue;
 import org.droidplanner.android.utils.file.IO.MissionReader;
 import org.droidplanner.android.utils.file.IO.MissionWriter;
+import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -50,7 +51,6 @@ public class MissionProxy implements DPMap.PathSource {
 
     public static final String ACTION_MISSION_PROXY_UPDATE = Utils.PACKAGE_NAME + ".ACTION_MISSION_PROXY_UPDATE";
 
-    private static final double DEFAULT_ALTITUDE = 20; //meters
     private static final int UNDO_BUFFER_SIZE = 30;
 
     private static final IntentFilter eventFilter = new IntentFilter();
@@ -89,6 +89,7 @@ public void onMissionItemsBuilt(MissionItem.ComplexItem[] complexItems) {
     private final List<MissionItemProxy> missionItemProxies = new ArrayList<MissionItemProxy>();
 
     private final LocalBroadcastManager lbm;
+    private final DroidPlannerPrefs dpPrefs;
     private Drone drone;
 
     private final CircularArray<Mission> undoBuffer = new CircularArray<>(UNDO_BUFFER_SIZE);
@@ -101,6 +102,8 @@ public MissionProxy(Context context, Drone drone) {
         this.currentMission = generateMission(true);
         lbm = LocalBroadcastManager.getInstance(context);
         lbm.registerReceiver(eventReceiver, eventFilter);
+
+        dpPrefs = new DroidPlannerPrefs(context);
     }
 
     public void setDrone(Drone drone){
@@ -259,7 +262,7 @@ public double getLastAltitude() {
             }
         }
 
-        return DEFAULT_ALTITUDE;
+        return dpPrefs.getDefaultAltitude();
     }
 
     /**
@@ -330,7 +333,7 @@ private void addMissionItem(int index, MissionItem missionItem) {
 
     public void addTakeoff() {
         Takeoff takeoff = new Takeoff();
-        takeoff.setTakeoffAltitude(10);
+        takeoff.setTakeoffAltitude(dpPrefs.getDefaultAltitude());
         addMissionItem(takeoff);
     }
 
diff --git a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionDetailFragment.java b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionDetailFragment.java
index 9e8d97da08..f07622f436 100644
--- a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionDetailFragment.java
+++ b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionDetailFragment.java
@@ -24,6 +24,7 @@
 import org.droidplanner.android.proxy.mission.MissionProxy;
 import org.droidplanner.android.proxy.mission.item.MissionItemProxy;
 import org.droidplanner.android.proxy.mission.item.adapters.AdapterMissionItems;
+import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 import org.droidplanner.android.widgets.spinners.SpinnerSelfSelect;
 
 import java.util.ArrayList;
@@ -36,8 +37,8 @@ public class MissionDetailFragment extends ApiListenerDialogFragment implements
 
     private static final String TAG = MissionDetailFragment.class.getSimpleName();
 
-    protected static final int MIN_ALTITUDE = -200; // meter
-    protected static final int MAX_ALTITUDE = +200; // meters
+    protected int MIN_ALTITUDE; // meter
+    protected int MAX_ALTITUDE; // meters
 
     public static final List<MissionItemType> typeWithNoMultiEditSupport = new
             ArrayList<MissionItemType>();
@@ -153,6 +154,10 @@ public static MissionDetailFragment newInstance(MissionItemType itemType) {
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setStyle(DialogFragment.STYLE_NO_TITLE, 0);
+
+        final DroidPlannerPrefs dpPrefs = getAppPrefs();
+        MIN_ALTITUDE = dpPrefs.getMinAltitude();
+        MAX_ALTITUDE = dpPrefs.getMaxAltitude();
     }
 
     @Override
diff --git a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionStructureScannerFragment.java b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionStructureScannerFragment.java
index 06723d3edf..1d6cae8859 100644
--- a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionStructureScannerFragment.java
+++ b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionStructureScannerFragment.java
@@ -74,7 +74,7 @@ public void onApiConnected() {
         CardWheelHorizontalView<LengthUnit> endAltitudeStepPicker = (CardWheelHorizontalView) view
                 .findViewById(R.id.heightStepPicker);
         endAltitudeStepPicker.setViewAdapter(new LengthWheelAdapter(context, R.layout.wheel_text_centered,
-                lengthUP.boxBaseValueToTarget(1), lengthUP.boxBaseValueToTarget(MAX_ALTITUDE)));
+                lengthUP.boxBaseValueToTarget(MIN_ALTITUDE), lengthUP.boxBaseValueToTarget(MAX_ALTITUDE)));
         endAltitudeStepPicker.addScrollListener(this);
 
         CardWheelHorizontalView<Integer> numberStepsPicker = (CardWheelHorizontalView<Integer>) view
diff --git a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionTakeoffFragment.java b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionTakeoffFragment.java
index 4fc135e583..a6aeaadc3e 100644
--- a/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionTakeoffFragment.java
+++ b/Android/src/org/droidplanner/android/proxy/mission/item/fragments/MissionTakeoffFragment.java
@@ -26,7 +26,7 @@ public void onApiConnected() {
 
         final LengthUnitProvider lengthUP = getLengthUnitProvider();
         final LengthWheelAdapter altitudeAdapter = new LengthWheelAdapter(getContext(), R.layout.wheel_text_centered,
-                lengthUP.boxBaseValueToTarget(0), lengthUP.boxBaseValueToTarget(MAX_ALTITUDE));
+                lengthUP.boxBaseValueToTarget(MIN_ALTITUDE), lengthUP.boxBaseValueToTarget(MAX_ALTITUDE));
         CardWheelHorizontalView<LengthUnit> cardAltitudePicker = (CardWheelHorizontalView) getView()
                 .findViewById(R.id.altitudePicker);
         cardAltitudePicker.setViewAdapter(altitudeAdapter);
diff --git a/Android/src/org/droidplanner/android/utils/NetworkUtils.java b/Android/src/org/droidplanner/android/utils/NetworkUtils.java
new file mode 100644
index 0000000000..ce555b5d24
--- /dev/null
+++ b/Android/src/org/droidplanner/android/utils/NetworkUtils.java
@@ -0,0 +1,59 @@
+package org.droidplanner.android.utils;
+
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.net.wifi.WifiInfo;
+import android.net.wifi.WifiManager;
+
+import com.squareup.okhttp.Cache;
+import com.squareup.okhttp.OkHttpClient;
+import com.squareup.okhttp.OkUrlFactory;
+
+import org.droidplanner.android.maps.providers.mapbox.MapboxUtils;
+
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+import javax.net.ssl.SSLSocketFactory;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/11/15.
+ */
+public class NetworkUtils {
+    public static boolean isNetworkAvailable(Context context) {
+        ConnectivityManager connectivityManager = (ConnectivityManager) context
+                .getSystemService(Context.CONNECTIVITY_SERVICE);
+        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
+        return activeNetworkInfo != null && activeNetworkInfo.isConnected();
+    }
+
+    public static String getCurrentWifiLink(Context context) {
+        final WifiManager wifiMgr = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
+
+        final WifiInfo connectedWifi = wifiMgr.getConnectionInfo();
+        final String connectedSSID = connectedWifi == null ? null : connectedWifi.getSSID().replace("\"", "");
+        return connectedSSID;
+    }
+
+    public static HttpURLConnection getHttpURLConnection(final URL url) {
+        return getHttpURLConnection(url, null, null);
+    }
+
+    public static HttpURLConnection getHttpURLConnection(final URL url, final Cache cache) {
+        return getHttpURLConnection(url, cache, null);
+    }
+
+    public static HttpURLConnection getHttpURLConnection(final URL url, final Cache cache, final SSLSocketFactory sslSocketFactory) {
+        OkHttpClient client = new OkHttpClient();
+        if (cache != null) {
+            client.setCache(cache);
+        }
+        if (sslSocketFactory != null) {
+            client.setSslSocketFactory(sslSocketFactory);
+        }
+        HttpURLConnection connection = new OkUrlFactory(client).open(url);
+        connection.setRequestProperty("User-Agent", MapboxUtils.getUserAgent());
+        return connection;
+    }
+}
diff --git a/Android/src/org/droidplanner/android/utils/Utils.java b/Android/src/org/droidplanner/android/utils/Utils.java
index a822fac35f..711cf6a7b0 100644
--- a/Android/src/org/droidplanner/android/utils/Utils.java
+++ b/Android/src/org/droidplanner/android/utils/Utils.java
@@ -3,10 +3,13 @@
 import android.content.Context;
 import android.content.res.Configuration;
 import android.content.res.Resources;
+import android.os.Looper;
 
 import org.droidplanner.android.maps.providers.DPMapProvider;
 import org.droidplanner.android.utils.prefs.DroidPlannerPrefs;
 
+import java.io.IOException;
+import java.io.Reader;
 import java.util.Locale;
 
 /**
@@ -47,4 +50,20 @@ public static void updateUILanguage(Context context) {
 			res.updateConfiguration(config, res.getDisplayMetrics());
 		}
 	}
+
+	public static boolean runningOnMainThread() {
+		return  Looper.myLooper() == Looper.getMainLooper();
+	}
+
+	public static String readAll(Reader rd) throws IOException {
+		StringBuilder sb = new StringBuilder();
+		int cp;
+		while ((cp = rd.read()) != -1) {
+			sb.append((char) cp);
+		}
+		return sb.toString();
+	}
+
+	//Private constructor to prevent instantiation.
+	private Utils(){}
 }
diff --git a/Android/src/org/droidplanner/android/utils/location/CheckLocationSettings.java b/Android/src/org/droidplanner/android/utils/location/CheckLocationSettings.java
new file mode 100644
index 0000000000..45198e5e67
--- /dev/null
+++ b/Android/src/org/droidplanner/android/utils/location/CheckLocationSettings.java
@@ -0,0 +1,184 @@
+package org.droidplanner.android.utils.location;
+
+import android.app.Activity;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.IntentSender;
+import android.os.Handler;
+import android.util.Log;
+import android.widget.Toast;
+
+import com.google.android.gms.common.ConnectionResult;
+import com.google.android.gms.common.GooglePlayServicesUtil;
+import com.google.android.gms.common.api.Api;
+import com.google.android.gms.common.api.GoogleApiClient;
+import com.google.android.gms.common.api.PendingResult;
+import com.google.android.gms.common.api.ResultCallback;
+import com.google.android.gms.common.api.Status;
+import com.google.android.gms.location.LocationRequest;
+import com.google.android.gms.location.LocationServices;
+import com.google.android.gms.location.LocationSettingsRequest;
+import com.google.android.gms.location.LocationSettingsResult;
+import com.google.android.gms.location.LocationSettingsStatusCodes;
+import com.o3dr.services.android.lib.util.googleApi.GoogleApiClientManager;
+
+import org.droidplanner.android.R;
+import org.droidplanner.android.activities.DrawerNavigationUI;
+import org.droidplanner.android.fragments.SettingsFragment;
+import org.droidplanner.android.fragments.control.BaseFlightControlFragment;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Created by Fredia Huya-Kouadio on 5/25/15.
+ */
+public class CheckLocationSettings implements GoogleApiClientManager.ManagerListener {
+
+    private static final String TAG = CheckLocationSettings.class.getSimpleName();
+
+    private final static Api<? extends Api.ApiOptions.NotRequiredOptions>[] apisList = new Api[]{LocationServices.API};
+
+    /**
+     * Used to ensure the correct location settings are set before starting follow me.
+     */
+    private final GoogleApiClientManager.GoogleApiClientTask checkLocationSettings = new GoogleApiClientManager.GoogleApiClientTask() {
+        @Override
+        protected void doRun() {
+            final GoogleApiClient googleApiClient = getGoogleApiClient();
+
+            LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
+                    .addLocationRequest(locationReq);
+
+            PendingResult<LocationSettingsResult> result =
+                    LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
+
+            result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
+                @Override
+                public void onResult(LocationSettingsResult locationSettingsResult) {
+                    final Status status = locationSettingsResult.getStatus();
+
+                    final DrawerNavigationUI activity = activityRef.get();
+                    switch (status.getStatusCode()) {
+                        case LocationSettingsStatusCodes.SUCCESS:
+                            if (onSuccess != null)
+                                onSuccess.run();
+                            break;
+
+                        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
+                            if (activity != null) {
+                                // Location settings are not satisfied. But could be fixed by showing the user
+                                // a dialog.
+                                try {
+                                    // Show the dialog by calling startResolutionForResult(),
+                                    // and check the result in onActivityResult().
+                                    status.startResolutionForResult(activity, BaseFlightControlFragment.FOLLOW_SETTINGS_UPDATE);
+                                } catch (IntentSender.SendIntentException e) {
+                                    // Ignore the error.
+                                    Log.e(TAG, e.getMessage(), e);
+                                }
+                            }
+                            break;
+
+                        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
+                            if (activity != null) {
+                                // Location settings are not satisfied. However, we have no way to fix the
+                                // settings so we won't show the dialog.
+                                Log.w(TAG, "Unable to get accurate user location.");
+                                Toast.makeText(activity, R.string.invalid_location_settings_warning, Toast.LENGTH_LONG).show();
+                            }
+                            break;
+                    }
+
+                    //Stop the google api client manager
+                    gapiMgr.stopSafely();
+                }
+            });
+        }
+    };
+
+    private final WeakReference<DrawerNavigationUI> activityRef;
+    private final LocationRequest locationReq;
+    private final Runnable onSuccess;
+    private final GoogleApiClientManager gapiMgr;
+
+    public CheckLocationSettings(DrawerNavigationUI activity, LocationRequest locationReq, Runnable onSuccess) {
+        activityRef = new WeakReference<>(activity);
+        this.locationReq = locationReq;
+        this.onSuccess = onSuccess;
+
+        gapiMgr = new GoogleApiClientManager(activity.getApplicationContext(), new Handler(), apisList);
+        gapiMgr.setManagerListener(this);
+    }
+
+    public void check() {
+        gapiMgr.start();
+    }
+
+    public void onReceive(Intent intent) {
+        switch (intent.getAction()) {
+            case SettingsFragment.ACTION_LOCATION_SETTINGS_UPDATED:
+                final int resultCode = intent.getIntExtra(SettingsFragment.EXTRA_RESULT_CODE, Activity.RESULT_OK);
+                switch (resultCode) {
+                    case Activity.RESULT_OK:
+                        // All required changes were successfully made. Try to acquire user location again
+                        if (onSuccess != null)
+                            onSuccess.run();
+                        break;
+
+                    case Activity.RESULT_CANCELED:
+                        // The user was asked to change settings, but chose not to
+                        final Activity activity = activityRef.get();
+                        if (activity != null) {
+                            Toast.makeText(activity, "Please update your location settings!", Toast.LENGTH_LONG)
+                                    .show();
+                        }
+                        break;
+
+                    default:
+                        break;
+                }
+                break;
+        }
+    }
+
+    @Override
+    public void onGoogleApiConnectionError(ConnectionResult connectionResult) {
+        final Activity activity = activityRef.get();
+        if (activity == null)
+            return;
+
+        if (connectionResult.hasResolution()) {
+            try {
+                connectionResult.startResolutionForResult(activity, 0);
+            } catch (IntentSender.SendIntentException e) {
+                //There was an error with the resolution intent. Try again.
+                gapiMgr.start();
+            }
+        } else {
+            onUnavailableGooglePlayServices(connectionResult.getErrorCode());
+        }
+    }
+
+    @Override
+    public void onUnavailableGooglePlayServices(int i) {
+        final Activity activity = activityRef.get();
+        if (activity != null) {
+            GooglePlayServicesUtil.showErrorDialogFragment(i, activity, 0, new DialogInterface.OnCancelListener() {
+                @Override
+                public void onCancel(DialogInterface dialog) {
+                    activity.finish();
+                }
+            });
+        }
+    }
+
+    @Override
+    public void onManagerStarted() {
+        gapiMgr.addTask(checkLocationSettings);
+    }
+
+    @Override
+    public void onManagerStopped() {
+
+    }
+}
diff --git a/Android/src/org/droidplanner/android/utils/prefs/DroidPlannerPrefs.java b/Android/src/org/droidplanner/android/utils/prefs/DroidPlannerPrefs.java
index 474baa0a51..e816fea264 100644
--- a/Android/src/org/droidplanner/android/utils/prefs/DroidPlannerPrefs.java
+++ b/Android/src/org/droidplanner/android/utils/prefs/DroidPlannerPrefs.java
@@ -3,11 +3,15 @@
 import java.util.UUID;
 
 import org.droidplanner.android.R;
+import org.droidplanner.android.utils.unit.UnitManager;
+import org.droidplanner.android.utils.unit.providers.length.LengthUnitProvider;
 import org.droidplanner.android.utils.unit.systems.UnitSystem;
 
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
+import android.support.annotation.IdRes;
+import android.support.annotation.StringRes;
 import android.text.TextUtils;
 import android.util.SparseBooleanArray;
 
@@ -52,8 +56,11 @@ public class DroidPlannerPrefs {
     private static final boolean DEFAULT_ENABLE_MAP_ROTATION = true;
     private static final boolean DEFAULT_ENABLE_KILL_SWITCH = false;
     private static final boolean DEFAULT_ENABLE_UDP_PING = false;
+	private static final int DEFAULT_MAX_ALT = 200; //meters
+	private static final int DEFAULT_MIN_ALT = 0; // meter
+	private static final int DEFAULT_ALT = 20; // meters
 
-    // Public for legacy usage
+	// Public for legacy usage
 	public SharedPreferences prefs;
 	private Context context;
 
@@ -196,7 +203,7 @@ public void setUdpServerPort(int serverPort){
 
     public int getUdpServerPort(){
         return Integer.parseInt(prefs.getString(context.getString(R.string
-                        .pref_udp_server_port_key), DEFAULT_UDP_SERVER_PORT));
+				.pref_udp_server_port_key), DEFAULT_UDP_SERVER_PORT));
     }
 
     public boolean isUdpPingEnabled(){
@@ -209,7 +216,7 @@ public String getUdpPingReceiverIp(){
 
     public int getUdpPingReceiverPort(){
         return Integer.parseInt(prefs.getString(context.getString(R.string.pref_udp_ping_receiver_port_key),
-                DEFAULT_UDP_SERVER_PORT));
+				DEFAULT_UDP_SERVER_PORT));
     }
 
     public String getBluetoothDeviceName(){
@@ -371,4 +378,42 @@ public boolean isAdvancedMenuEnabled(){
     public boolean isKillSwitchEnabled(){
         return prefs.getBoolean(context.getString(R.string.pref_enable_kill_switch_key), DEFAULT_ENABLE_KILL_SWITCH);
     }
+
+	/**
+	 * @return the max altitude in meters
+	 */
+	public int getMaxAltitude(){
+		return getAltitudePreference(R.string.pref_alt_max_value_key, DEFAULT_MAX_ALT);
+	}
+
+	/**
+	 * @return the min altitude in meters
+	 */
+	public int getMinAltitude(){
+		return getAltitudePreference(R.string.pref_alt_min_value_key, DEFAULT_MIN_ALT);
+	}
+
+	/**
+	 * @return the default starting altitude in meters
+	 */
+	public int getDefaultAltitude(){
+		return getAltitudePreference(R.string.pref_alt_default_value_key, DEFAULT_ALT);
+	}
+
+	public void setAltitudePreference(@StringRes int prefKeyRes, int altitude){
+		prefs.edit().putString(context.getString(prefKeyRes), String.valueOf(altitude)).apply();
+	}
+
+	private int getAltitudePreference(@StringRes int prefKeyRes, int defaultValue){
+		final String maxAltValue = prefs.getString(context.getString(prefKeyRes), null);
+		if(TextUtils.isEmpty(maxAltValue))
+			return defaultValue;
+
+		try {
+			final int maxAlt = Integer.parseInt(maxAltValue);
+			return maxAlt;
+		}catch(Exception e){
+			return defaultValue;
+		}
+	}
 }
diff --git a/Android/src/org/droidplanner/android/utils/unit/providers/length/ImperialLengthUnitProvider.java b/Android/src/org/droidplanner/android/utils/unit/providers/length/ImperialLengthUnitProvider.java
index 73c1a516c9..44d7fd02a6 100644
--- a/Android/src/org/droidplanner/android/utils/unit/providers/length/ImperialLengthUnitProvider.java
+++ b/Android/src/org/droidplanner/android/utils/unit/providers/length/ImperialLengthUnitProvider.java
@@ -2,7 +2,9 @@
 
 import org.beyene.sius.operation.Operation;
 import org.beyene.sius.unit.UnitIdentifier;
+import org.beyene.sius.unit.impl.FactoryLength;
 import org.beyene.sius.unit.length.Constants;
+import org.beyene.sius.unit.length.Foot;
 import org.beyene.sius.unit.length.LengthUnit;
 import org.beyene.sius.unit.length.Meter;
 
@@ -19,4 +21,11 @@ public LengthUnit fromBaseToTarget(Meter base) {
         else
             return Operation.convert(base, UnitIdentifier.FOOT);
     }
+
+    @Override
+    public LengthUnit boxTargetValue(double valueInTargetUnits) {
+        return FactoryLength.foot(valueInTargetUnits);
+    }
+
+
 }
diff --git a/Android/src/org/droidplanner/android/utils/unit/providers/length/LengthUnitProvider.java b/Android/src/org/droidplanner/android/utils/unit/providers/length/LengthUnitProvider.java
index 2f2d7d5a3a..20ae29c41e 100644
--- a/Android/src/org/droidplanner/android/utils/unit/providers/length/LengthUnitProvider.java
+++ b/Android/src/org/droidplanner/android/utils/unit/providers/length/LengthUnitProvider.java
@@ -28,4 +28,10 @@ public Meter fromTargetToBase(LengthUnit target) {
 
         return Operation.convert(target, UnitIdentifier.METER);
     }
+
+    public Meter fromTargetToBase(double valueInTargetUnits){
+        return fromTargetToBase(boxTargetValue(valueInTargetUnits));
+    }
+
+    public abstract LengthUnit boxTargetValue(double valueInTargetUnits);
 }
diff --git a/Android/src/org/droidplanner/android/utils/unit/providers/length/MetricLengthUnitProvider.java b/Android/src/org/droidplanner/android/utils/unit/providers/length/MetricLengthUnitProvider.java
index a9c75187a3..182fb571db 100644
--- a/Android/src/org/droidplanner/android/utils/unit/providers/length/MetricLengthUnitProvider.java
+++ b/Android/src/org/droidplanner/android/utils/unit/providers/length/MetricLengthUnitProvider.java
@@ -2,6 +2,7 @@
 
 import org.beyene.sius.operation.Operation;
 import org.beyene.sius.unit.UnitIdentifier;
+import org.beyene.sius.unit.impl.FactoryLength;
 import org.beyene.sius.unit.length.Constants;
 import org.beyene.sius.unit.length.LengthUnit;
 import org.beyene.sius.unit.length.Meter;
@@ -19,4 +20,9 @@ public LengthUnit fromBaseToTarget(Meter base) {
         else
             return base;
     }
+
+    @Override
+    public LengthUnit boxTargetValue(double valueInTargetUnits) {
+        return FactoryLength.meter(valueInTargetUnits);
+    }
 }