diff --git a/OpenKeychain/src/main/AndroidManifest.xml b/OpenKeychain/src/main/AndroidManifest.xml
index 83d8bce91..35048b936 100644
--- a/OpenKeychain/src/main/AndroidManifest.xml
+++ b/OpenKeychain/src/main/AndroidManifest.xml
@@ -9,15 +9,15 @@
         ===============
         - Last APG 1 version was 10900 (1.0.9 beta 00)
         - Keychain starting with versionCode 20000!
-        
+
         Association of file types to Keychain
         =====================================
         General remarks about file ending conventions:
         - *.gpg,*.pgp for binary files
         - *.asc for ascii armored files The actual content can be anything.
-        
+
         The file ending only shows if it is binary or ascii encoded.
-        
+
         Remarks about the ugly android:pathPattern:
         - We are matching all files with a specific file ending.
         This is done in an ugly way because of Android limitations.
@@ -73,7 +73,7 @@
         android:hardwareAccelerated="true"
         android:icon="@drawable/ic_launcher"
         android:label="@string/app_name"
-        android:theme="@style/KeychainTheme">
+        android:theme="@style/LightTheme">
         <activity
             android:name=".ui.MainActivity"
             android:configChanges="orientation|screenSize|keyboardHidden|keyboard"
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
index 621387ca2..a45cac832 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/Constants.java
@@ -103,6 +103,7 @@ public final class Constants {
         public static final String PROXY_HOST = "proxyHost";
         public static final String PROXY_PORT = "proxyPort";
         public static final String PROXY_TYPE = "proxyType";
+        public static final String THEME = "theme";
     }
 
     /**
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
index bcf42ba74..27ce3ac56 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/SettingsActivity.java
@@ -53,6 +53,7 @@ public class SettingsActivity extends AppCompatPreferenceActivity {
     public static final String ACTION_PREFS_CLOUD = "org.sufficientlysecure.keychain.ui.PREFS_CLOUD";
     public static final String ACTION_PREFS_ADV = "org.sufficientlysecure.keychain.ui.PREFS_ADV";
     public static final String ACTION_PREFS_PROXY = "org.sufficientlysecure.keychain.ui.PREFS_PROXY";
+    public static final String ACTION_PREFS_GUI = "org.sufficientlysecure.keychain.ui.PREFS_GUI";
 
     public static final int REQUEST_CODE_KEYSERVER_PREF = 0x00007005;
 
@@ -106,6 +107,10 @@ public class SettingsActivity extends AppCompatPreferenceActivity {
             initializeUseNumKeypadForYubiKeyPin(
                     (CheckBoxPreference) findPreference(Constants.Pref.USE_NUMKEYPAD_FOR_YUBIKEY_PIN));
 
+        } else if (action != null && action.equals(ACTION_PREFS_GUI)) {
+            addPreferencesFromResource(R.xml.gui_preferences);
+
+            initializeTheme((ListPreference) findPreference(Constants.Pref.THEME));
         }
     }
 
@@ -425,14 +430,30 @@ public class SettingsActivity extends AppCompatPreferenceActivity {
                 mUseTor.setEnabled(true);
             }
         }
-
     }
 
-    @TargetApi(Build.VERSION_CODES.KITKAT)
+    /**
+     * This fragment shows gui preferences.
+     */
+    public static class GuiPrefsFragment extends PreferenceFragment {
+
+        @Override
+        public void onCreate(Bundle savedInstanceState) {
+            super.onCreate(savedInstanceState);
+
+
+            // Load the preferences from an XML resource
+            addPreferencesFromResource(R.xml.gui_preferences);
+
+            initializeTheme((ListPreference) findPreference(Constants.Pref.THEME));
+        }
+    }
+
     protected boolean isValidFragment(String fragmentName) {
         return AdvancedPrefsFragment.class.getName().equals(fragmentName)
                 || CloudSearchPrefsFragment.class.getName().equals(fragmentName)
                 || ProxyPrefsFragment.class.getName().equals(fragmentName)
+                || GuiPrefsFragment.class.getName().equals(fragmentName)
                 || super.isValidFragment(fragmentName);
     }
 
@@ -461,6 +482,19 @@ public class SettingsActivity extends AppCompatPreferenceActivity {
                 });
     }
 
+    private static void initializeTheme(final ListPreference mTheme) {
+        mTheme.setValue(sPreferences.getTheme());
+        mTheme.setSummary(mTheme.getEntry());
+        mTheme.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
+            public boolean onPreferenceChange(Preference preference, Object newValue) {
+                mTheme.setValue((String) newValue);
+                mTheme.setSummary(mTheme.getEntry());
+                sPreferences.setTheme((String) newValue);
+                return false;
+            }
+        });
+    }
+
     private static void initializeSearchKeyserver(final CheckBoxPreference mSearchKeyserver) {
         Preferences.CloudSearchPrefs prefs = sPreferences.getCloudSearchPrefs();
         mSearchKeyserver.setChecked(prefs.searchKeyserver);
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/BaseActivity.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/BaseActivity.java
index 9529d8689..82f62f933 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/BaseActivity.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/BaseActivity.java
@@ -22,6 +22,7 @@ import android.os.Bundle;
 import android.support.v7.app.ActionBar;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
+import android.view.ContextThemeWrapper;
 import android.view.Gravity;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -29,6 +30,7 @@ import android.view.ViewGroup;
 import android.widget.TextView;
 
 import org.sufficientlysecure.keychain.R;
+import org.sufficientlysecure.keychain.util.Preferences;
 
 /**
  * Setups Toolbar
@@ -36,9 +38,19 @@ import org.sufficientlysecure.keychain.R;
 public abstract class BaseActivity extends AppCompatActivity {
     protected Toolbar mToolbar;
     protected View mStatusBar;
+    private static Preferences sPreferences;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
+        sPreferences = Preferences.getPreferences(this);
+        int themeId = R.style.LightTheme;
+        if ("dark".equals(sPreferences.getTheme())) {
+            themeId = R.style.DarkTheme;
+        }
+
+        ContextThemeWrapper w = new ContextThemeWrapper(this, themeId);
+        getTheme().setTo(w.getTheme());
+
         super.onCreate(savedInstanceState);
         initLayout();
         initToolbar();
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
index c13c07503..c7b02f696 100644
--- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
+++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/util/Preferences.java
@@ -220,6 +220,15 @@ public class Preferences {
         return mSharedPreferences.getBoolean(Pref.TEXT_USE_COMPRESSION, true);
     }
 
+    public String getTheme() {
+        return mSharedPreferences.getString(Pref.THEME, "light");
+    }
+
+    public void setTheme(String value) {
+        SharedPreferences.Editor editor = mSharedPreferences.edit();
+        editor.putString(Constants.Pref.THEME, value);
+        editor.commit();
+    }
 
     public void setUseArmor(boolean useArmor) {
         SharedPreferences.Editor editor = mSharedPreferences.edit();
diff --git a/OpenKeychain/src/main/res/values-v21/themes.xml b/OpenKeychain/src/main/res/values-v21/themes.xml
index b47026e5b..dab38f97a 100644
--- a/OpenKeychain/src/main/res/values-v21/themes.xml
+++ b/OpenKeychain/src/main/res/values-v21/themes.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 
-    <style name="KeychainTheme" parent="KeychainTheme.Base">
+    <style name="LightTheme" parent="LightBaseTheme">
         <item name="android:windowTranslucentStatus">true</item>
 
         <!-- enable window content transitions -->
@@ -12,4 +12,17 @@
         <item name="android:windowSharedElementExitTransition">@android:transition/move</item>
 
     </style>
-</resources>
\ No newline at end of file
+
+     <style name="DarkTheme" parent="DarkBaseTheme">
+        <item name="android:windowTranslucentStatus">true</item>
+
+        <!-- enable window content transitions -->
+        <item name="android:windowContentTransitions">true</item>
+        <item name="android:windowAllowEnterTransitionOverlap">true</item>
+        <item name="android:windowAllowReturnTransitionOverlap">true</item>
+        <item name="android:windowSharedElementEnterTransition">@android:transition/move</item>
+        <item name="android:windowSharedElementExitTransition">@android:transition/move</item>
+
+    </style>
+
+</resources>
diff --git a/OpenKeychain/src/main/res/values/arrays.xml b/OpenKeychain/src/main/res/values/arrays.xml
index a9f521b17..ef3970672 100644
--- a/OpenKeychain/src/main/res/values/arrays.xml
+++ b/OpenKeychain/src/main/res/values/arrays.xml
@@ -61,4 +61,12 @@
         <item>@string/key_size_custom</item>
     </string-array>
 
+    <string-array name="theme_entries" translatable="false">
+        <item>@string/theme_dark</item>
+        <item>@string/theme_light</item>
+    </string-array>
+    <string-array name="theme_values" translatable="false">
+        <item>"dark"</item>
+        <item>"ligh"</item>
+    </string-array>
 </resources>
diff --git a/OpenKeychain/src/main/res/values/strings.xml b/OpenKeychain/src/main/res/values/strings.xml
index db81963c1..faa9aa39c 100644
--- a/OpenKeychain/src/main/res/values/strings.xml
+++ b/OpenKeychain/src/main/res/values/strings.xml
@@ -50,6 +50,7 @@
     <string name="section_cloud_search">"Cloud search"</string>
     <string name="section_passphrase_cache">"Password/PIN Handling"</string>
     <string name="section_proxy_settings">"Proxy Settings"</string>
+    <string name="section_gui">"Interface"</string>
     <string name="section_certify">"Confirm"</string>
     <string name="section_actions">"Actions"</string>
     <string name="section_share_key">"Key"</string>
@@ -167,6 +168,7 @@
     <string name="label_verify_keyserver">"Verify keyserver"</string>
     <string name="label_enter_keyserver_url">"Enter keyserver URL"</string>
     <string name="label_keyserver_dialog_delete">"Delete keyserver"</string>
+    <string name="label_theme">"Theme"</string>
 
     <string name="pref_keyserver">"OpenPGP keyservers"</string>
     <string name="pref_keyserver_summary">"Search keys on selected OpenPGP keyservers (HKP protocol)"</string>
@@ -245,6 +247,8 @@
     <string name="filemanager_title_open">"Open…"</string>
     <string name="error">"Error"</string>
     <string name="error_message">"Error: %s"</string>
+    <string name="theme_dark">"Dark"</string>
+    <string name="theme_light">"Light"</string>
 
     <!-- key flags -->
     <string name="flag_certify">"Certify"</string>
diff --git a/OpenKeychain/src/main/res/values/themes.xml b/OpenKeychain/src/main/res/values/themes.xml
index 8e0ea6ac0..d15106966 100644
--- a/OpenKeychain/src/main/res/values/themes.xml
+++ b/OpenKeychain/src/main/res/values/themes.xml
@@ -1,9 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 
-    <style name="KeychainTheme" parent="KeychainTheme.Base" />
-
-    <style name="KeychainTheme.Base" parent="Theme.AppCompat.Light">
+    <style name="LightBaseTheme" parent="Theme.AppCompat.Light">
         <item name="colorPrimary">@color/primary</item>
         <item name="colorPrimaryDark">@color/primary_dark</item>
         <item name="colorAccent">@color/accent</item>
@@ -16,6 +14,25 @@
         <item name="searchViewStyle">@style/MySearchViewStyle</item>
     </style>
 
+    <style name="DarkBaseTheme" parent="Theme.AppCompat">
+        <item name="colorPrimary">@color/primary</item>
+        <item name="colorPrimaryDark">@color/primary_dark</item>
+        <item name="colorAccent">@color/accent</item>
+
+        <!-- remove actionbar and title, we use toolbar! -->
+        <item name="windowNoTitle">true</item>
+        <item name="windowActionBar">false</item>
+        <!-- multi selection should overlay Toolbar! http://stackoverflow.com/a/26450875 -->
+        <item name="windowActionModeOverlay">true</item>
+        <item name="searchViewStyle">@style/MySearchViewStyle</item>
+    </style>
+
+    <style name="LightTheme" parent="LightBaseTheme">
+    </style>
+
+    <style name="DarkTheme" parent="DarkBaseTheme">
+    </style>
+
     <!-- http://android-developers.blogspot.de/2014/10/appcompat-v21-material-design-for-pre.html -->
     <style name="MySearchViewStyle" parent="Widget.AppCompat.SearchView">
         <!-- Background for the search query section (e.g. EditText) -->
@@ -40,4 +57,4 @@
         <item name="windowActionBar">false</item>
         <item name="windowNoTitle">true</item>
     </style>
-</resources>
\ No newline at end of file
+</resources>
diff --git a/OpenKeychain/src/main/res/xml/gui_preferences.xml b/OpenKeychain/src/main/res/xml/gui_preferences.xml
new file mode 100644
index 000000000..cda7beeef
--- /dev/null
+++ b/OpenKeychain/src/main/res/xml/gui_preferences.xml
@@ -0,0 +1,10 @@
+<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
+    <ListPreference
+        android:persistent="false"
+        android:key="theme"
+        android:title="@string/label_theme"
+        android:entries="@array/theme_entries"
+        android:entryValues="@array/theme_values"
+        android:dialogTitle="@string/label_theme" />
+
+</PreferenceScreen>
diff --git a/OpenKeychain/src/main/res/xml/preference_headers.xml b/OpenKeychain/src/main/res/xml/preference_headers.xml
index 70e400567..7a0ea18bb 100644
--- a/OpenKeychain/src/main/res/xml/preference_headers.xml
+++ b/OpenKeychain/src/main/res/xml/preference_headers.xml
@@ -1,4 +1,7 @@
 <preference-headers xmlns:android="http://schemas.android.com/apk/res/android">
+    <header
+        android:fragment="org.sufficientlysecure.keychain.ui.SettingsActivity$GuiPrefsFragment"
+        android:title="@string/section_gui" />
     <header
         android:fragment="org.sufficientlysecure.keychain.ui.SettingsActivity$CloudSearchPrefsFragment"
         android:title="@string/section_cloud_search" />