diff --git a/app/build.gradle b/app/build.gradle
index 01ba6f9..99299a0 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -36,6 +36,9 @@ dependencies {
     compile('com.mikepenz:materialdrawer:3.1.0@aar') {
         transitive = true
     }
+    compile('com.mikepenz:aboutlibraries:5.3.4@aar') {
+        transitive = true
+    }
     compile 'com.mikepenz:iconics:1.6.2@aar'
     compile 'com.mikepenz:community-material-typeface:1.1.71@aar'
 }
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 979915d..4f64223 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -3,6 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     package="ch.dissem.apps.abit">
 
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
@@ -128,6 +129,13 @@
             <meta-data android:name="android.content.SyncAdapter"
                 android:resource="@xml/syncadapter" />
         </service>
+
+        <!-- Receive Wi-Fi connection state changes -->
+        <receiver android:name=".listener.WifiReceiver">
+            <intent-filter>
+                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
+            </intent-filter>
+        </receiver>
     </application>
 
 </manifest>
diff --git a/app/src/main/java/ch/dissem/apps/abit/MainActivity.java b/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
index 5d7bee8..1d2a418 100644
--- a/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
+++ b/app/src/main/java/ch/dissem/apps/abit/MainActivity.java
@@ -1,10 +1,9 @@
 package ch.dissem.apps.abit;
 
-import android.accounts.Account;
-import android.accounts.AccountManager;
+import android.app.AlertDialog;
 import android.content.ComponentName;
-import android.content.ContentResolver;
 import android.content.Context;
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.ServiceConnection;
 import android.os.Bundle;
@@ -49,7 +48,6 @@ import ch.dissem.apps.abit.listener.ActionBarListener;
 import ch.dissem.apps.abit.listener.ListSelectionListener;
 import ch.dissem.apps.abit.service.BitmessageService;
 import ch.dissem.apps.abit.service.Singleton;
-import ch.dissem.apps.abit.synchronization.Authenticator;
 import ch.dissem.apps.abit.synchronization.SyncAdapter;
 import ch.dissem.apps.abit.util.Preferences;
 import ch.dissem.bitmessage.entity.BitmessageAddress;
@@ -61,7 +59,6 @@ import ch.dissem.bitmessage.ports.MessageRepository;
 import static ch.dissem.apps.abit.service.BitmessageService.DATA_FIELD_IDENTITY;
 import static ch.dissem.apps.abit.service.BitmessageService.MSG_START_NODE;
 import static ch.dissem.apps.abit.service.BitmessageService.MSG_STOP_NODE;
-import static ch.dissem.apps.abit.synchronization.StubProvider.AUTHORITY;
 
 
 /**
@@ -300,12 +297,7 @@ public class MainActivity extends AppCompatActivity
                                                                  boolean isChecked) {
                                         if (messenger != null) {
                                             if (isChecked) {
-                                                try {
-                                                    service.send(Message.obtain(null,
-                                                            MSG_START_NODE));
-                                                } catch (RemoteException e) {
-                                                    LOG.error(e.getMessage(), e);
-                                                }
+                                                checkAndStartNode(buttonView);
                                             } else {
                                                 try {
                                                     service.send(Message.obtain(null,
@@ -358,6 +350,37 @@ public class MainActivity extends AppCompatActivity
                 .build();
     }
 
+    private void checkAndStartNode(final CompoundButton buttonView) {
+        if (Preferences.isConnectionAllowed(MainActivity.this)) {
+            forceStartNode();
+        } else {
+            new AlertDialog.Builder(MainActivity.this)
+                    .setMessage(R.string.full_node_warning)
+                    .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            forceStartNode();
+                        }
+                    })
+                    .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
+                        @Override
+                        public void onClick(DialogInterface dialog, int which) {
+                            buttonView.setChecked(false);
+                        }
+                    })
+                    .show();
+        }
+    }
+
+    private void forceStartNode() {
+        try {
+            service.send(Message.obtain(null,
+                    MSG_START_NODE));
+        } catch (RemoteException e) {
+            LOG.error(e.getMessage(), e);
+        }
+    }
+
     private void showSelectedLabel() {
         if (getSupportFragmentManager().findFragmentById(R.id.item_list) instanceof
                 MessageListFragment) {
diff --git a/app/src/main/java/ch/dissem/apps/abit/SettingsFragment.java b/app/src/main/java/ch/dissem/apps/abit/SettingsFragment.java
index 75bd0bc..d92ac68 100644
--- a/app/src/main/java/ch/dissem/apps/abit/SettingsFragment.java
+++ b/app/src/main/java/ch/dissem/apps/abit/SettingsFragment.java
@@ -3,9 +3,13 @@ package ch.dissem.apps.abit;
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.os.Bundle;
+import android.preference.Preference;
 import android.preference.PreferenceFragment;
 import android.preference.PreferenceManager;
 
+import com.mikepenz.aboutlibraries.Libs;
+import com.mikepenz.aboutlibraries.LibsBuilder;
+
 import ch.dissem.apps.abit.synchronization.SyncAdapter;
 
 import static ch.dissem.apps.abit.util.Constants.PREFERENCE_SERVER_POW;
@@ -23,6 +27,20 @@ public class SettingsFragment
 
         // Load the preferences from an XML resource
         addPreferencesFromResource(R.xml.preferences);
+
+        Preference about = findPreference("about");
+        about.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
+            @Override
+            public boolean onPreferenceClick(Preference preference) {
+                new LibsBuilder()
+                        .withActivityStyle(Libs.ActivityStyle.LIGHT_DARK_TOOLBAR)
+                        .withAboutIconShown(true)
+                        .withAboutVersionShown(true)
+                        .withAboutDescription(getString(R.string.about_app))
+                        .start(getActivity());
+                return true;
+            }
+        });
     }
 
     @Override
diff --git a/app/src/main/java/ch/dissem/apps/abit/listener/WifiReceiver.java b/app/src/main/java/ch/dissem/apps/abit/listener/WifiReceiver.java
new file mode 100644
index 0000000..ca34809
--- /dev/null
+++ b/app/src/main/java/ch/dissem/apps/abit/listener/WifiReceiver.java
@@ -0,0 +1,39 @@
+package ch.dissem.apps.abit.listener;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.net.wifi.SupplicantState;
+import android.net.wifi.WifiManager;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import ch.dissem.apps.abit.service.Singleton;
+import ch.dissem.apps.abit.util.Preferences;
+import ch.dissem.bitmessage.BitmessageContext;
+
+public class WifiReceiver extends BroadcastReceiver {
+    @Override
+    public void onReceive(Context ctx, Intent intent) {
+        if (Preferences.isWifiOnly(ctx)) {
+            BitmessageContext bmc = Singleton.getBitmessageContext(ctx);
+            ConnectivityManager conMan = (ConnectivityManager) ctx.getSystemService(Context
+                    .CONNECTIVITY_SERVICE);
+            NetworkInfo netInfo = conMan.getActiveNetworkInfo();
+
+            if (netInfo != null && netInfo.getType() != ConnectivityManager.TYPE_WIFI
+                    && !bmc.isRunning()) {
+                bmc.shutdown();
+            }
+        }
+    }
+
+    public static boolean isConnectedToWifi(Context ctx) {
+        WifiManager wifiManager = (WifiManager) ctx.getSystemService(Context.WIFI_SERVICE);
+        SupplicantState state = wifiManager.getConnectionInfo().getSupplicantState();
+        return state == SupplicantState.COMPLETED;
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java b/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
index d2184fd..5c81472 100644
--- a/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
+++ b/app/src/main/java/ch/dissem/apps/abit/service/BitmessageService.java
@@ -157,12 +157,17 @@ public class BitmessageService extends Service {
                     // (I'm not quite sure this can be done here, though)
                     service.get().startService(new Intent(service.get(), BitmessageService.class));
                     running = true;
-                    service.get().startForeground(ONGOING_NOTIFICATION_ID, notification.getNotification());
-                    bmc.startup();
+                    service.get().startForeground(ONGOING_NOTIFICATION_ID, notification
+                            .getNotification());
+                    if (!bmc.isRunning()) {
+                        bmc.startup();
+                    }
                     notification.show();
                     break;
                 case MSG_STOP_NODE:
-                    bmc.shutdown();
+                    if (bmc.isRunning()) {
+                        bmc.shutdown();
+                    }
                     running = false;
                     service.get().stopForeground(false);
                     service.get().stopSelf();
diff --git a/app/src/main/java/ch/dissem/apps/abit/synchronization/SyncAdapter.java b/app/src/main/java/ch/dissem/apps/abit/synchronization/SyncAdapter.java
index 682e165..7655044 100644
--- a/app/src/main/java/ch/dissem/apps/abit/synchronization/SyncAdapter.java
+++ b/app/src/main/java/ch/dissem/apps/abit/synchronization/SyncAdapter.java
@@ -52,12 +52,15 @@ public class SyncAdapter extends AbstractThreadedSyncAdapter {
     @Override
     public void onPerformSync(Account account, Bundle extras, String authority,
                               ContentProviderClient provider, SyncResult syncResult) {
-        if (account.equals(Authenticator.ACCOUNT_SYNC))
-            syncData();
-        else if (account.equals(Authenticator.ACCOUNT_POW))
+        if (account.equals(Authenticator.ACCOUNT_SYNC)) {
+            if (Preferences.isConnectionAllowed(getContext())) {
+                syncData();
+            }
+        } else if (account.equals(Authenticator.ACCOUNT_POW)) {
             syncPOW();
-        else
+        } else {
             throw new RuntimeException("Unknown " + account);
+        }
     }
 
     private void syncData() {
diff --git a/app/src/main/java/ch/dissem/apps/abit/util/Preferences.java b/app/src/main/java/ch/dissem/apps/abit/util/Preferences.java
index 20c5862..df5b1c7 100644
--- a/app/src/main/java/ch/dissem/apps/abit/util/Preferences.java
+++ b/app/src/main/java/ch/dissem/apps/abit/util/Preferences.java
@@ -11,14 +11,15 @@ import java.net.InetAddress;
 import java.net.UnknownHostException;
 
 import ch.dissem.apps.abit.R;
+import ch.dissem.apps.abit.listener.WifiReceiver;
 import ch.dissem.apps.abit.notification.ErrorNotification;
 
-import static ch.dissem.apps.abit.util.Constants.PREFERENCE_SERVER_POW;
 import static ch.dissem.apps.abit.util.Constants.PREFERENCE_SYNC_TIMEOUT;
 import static ch.dissem.apps.abit.util.Constants.PREFERENCE_TRUSTED_NODE;
+import static ch.dissem.apps.abit.util.Constants.PREFERENCE_WIFI_ONLY;
 
 /**
- * Created by chrig on 01.12.2015.
+ * @author Christian Basler
  */
 public class Preferences {
     private static Logger LOG = LoggerFactory.getLogger(Preferences.class);
@@ -77,14 +78,18 @@ public class Preferences {
         return preference == null ? 120 : Long.parseLong(preference);
     }
 
-    public static boolean isServerPOW(Context ctx) {
-        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(ctx);
-        return preferences.getBoolean(PREFERENCE_SERVER_POW, false);
-    }
-
     private static String getPreference(Context ctx, String name) {
         SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(ctx);
 
         return preferences.getString(name, null);
     }
+
+    public static boolean isConnectionAllowed(Context ctx) {
+        return !isWifiOnly(ctx) || WifiReceiver.isConnectedToWifi(ctx);
+    }
+
+    public static boolean isWifiOnly(Context ctx) {
+        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(ctx);
+        return preferences.getBoolean(PREFERENCE_WIFI_ONLY, true);
+    }
 }
diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index 19fda0d..694b211 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -51,4 +51,5 @@
     <string name="subscribed">Abonniert</string>
     <string name="server_pow">Server POW</string>
     <string name="server_pow_summary">Der vertrauenswürdige Knoten macht den Proof of Work</string>
+    <string name="full_node_warning">Ein aktiver Bitmessage-Knoten muss viel hoch- und herunterladen, was auf einem mobilen Netzwerk teuer sein kann. Soll tatsächlich ein aktiver Knoten gestartet werden?</string>
 </resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index eb1f6e8..2920668 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -10,4 +10,9 @@
   <color name="secondary_text">#727272</color>
   <color name="icons">#212121</color>
   <color name="divider">#B6B6B6</color>
+
+  <!-- Used for AboutLibraries -->
+  <color name="colorPrimary">@color/primary</color>
+  <color name="colorPrimaryDark">@color/primary_dark</color>
+  <color name="colorAccent">@color/accent</color>
 </resources>
diff --git a/app/src/main/res/values/library_jabit_strings.xml b/app/src/main/res/values/library_jabit_strings.xml
new file mode 100644
index 0000000..bd4220c
--- /dev/null
+++ b/app/src/main/res/values/library_jabit_strings.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="define_jabit"></string>
+    <!-- Author section -->
+    <string name="library_jabit_author">Christian Basler</string>
+    <string name="library_jabit_authorWebsite">dissem.ch</string>
+    <!-- Library section -->
+    <string name="library_jabit_libraryName">Jabit</string>
+    <string name="library_jabit_libraryDescription">Jabit strives to be an easy to use Bitmessage library for Java developers to quickly implement their own Bitmessage clients.</string>
+    <string name="library_jabit_libraryWebsite">https://github.com/Dissem/Jabit/wiki</string>
+    <string name="library_jabit_libraryVersion">1.0.0</string>
+    <!-- OpenSource section -->
+    <string name="library_jabit_isOpenSource">true</string>
+    <string name="library_jabit_repositoryLink">https://github.com/Dissem/Jabit</string>
+    <!-- ClassPath for autoDetect section -->
+    <string name="library_jabit_classPath">ch.dissem.bitmessage.BitmessageContext</string>
+    <!-- License section -->
+    <string name="library_jabit_licenseId">apache_2_0</string>
+    <!-- Custom variables section -->
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 19fd4f8..5746bbd 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,5 +1,6 @@
 <resources>
     <string name="app_name">Abit</string>
+    <string name="about_app">A Bitmessage client for Android</string>
     <string name="title_message_detail">Message Detail</string>
     <string name="title_subscription_detail">Subscription Detail</string>
     <string name="bitmessage_full_node">Bitmessage Node</string>
@@ -51,4 +52,7 @@
     <string name="subscribed">Subscribed</string>
     <string name="server_pow">Server POW</string>
     <string name="server_pow_summary">Trusted node does proof of work</string>
+    <string name="full_node_warning">Running a full Bitmessage uses a lot of traffic, which could be expensive on a mobile network. Are you sure you want to start a full node?</string>
+    <string name="about">About Abit</string>
+    <string name="about_summary">Open source dependencies.</string>
 </resources>
diff --git a/app/src/main/res/xml/preferences.xml b/app/src/main/res/xml/preferences.xml
index 50fea51..696d443 100644
--- a/app/src/main/res/xml/preferences.xml
+++ b/app/src/main/res/xml/preferences.xml
@@ -31,4 +31,9 @@
         android:title="@string/server_pow"
         android:summary="@string/server_pow_summary"
         />
+    <Preference
+        android:key="about"
+        android:title="@string/about"
+        android:summary="@string/about_summary"
+        />
 </PreferenceScreen>
\ No newline at end of file