diff --git a/app/src/main/res/values-de/strings.xml b/app/src/main/res/values-de/strings.xml
index 1285f24..05fbbd2 100644
--- a/app/src/main/res/values-de/strings.xml
+++ b/app/src/main/res/values-de/strings.xml
@@ -10,6 +10,9 @@
 
     <!-- Strings related to Settings -->
     <string name="title_activity_settings">Einstellungen</string>
+    <string name="pref_dark_mode">Nachtmodus</string>
+    <string name="pref_dark_mode_setting">Nachtmodus</string>
+    <string name="pref_dark_mode_summary">Wechsel zwischen Tages und Nacht Modus</string>
 
     <!-- About Page -->
     <string name="about_affiliation">In Zusammenarbeit mit:</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 7a89e2c..1334060 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -30,6 +30,7 @@
     <string name="pref_group_highlight_value">Value highlight</string>
     <string name="pref_highlight_vals">Same values</string>
     <string name="pref_highlight_notes">Notes</string>
+
     <!-- #Game -->
     <string name="pref_header_game">Game</string>
     <string name="pref_group_game">Game settings</string>
@@ -54,6 +55,10 @@
     <string name="pref_automatic_note_deletion_summary">Automatically remove notes when setting values on connected cells</string>
     <string name="pref_timer_reset">Timer Reset</string>
     <string name="pref_timer_reset_summary">Also reset the timer, when resetting the game board.</string>
+    <string name="pref_dark_mode">Dark Mode</string>
+
+    <string name="pref_dark_mode_setting">Dark Theme</string>
+    <string name="pref_dark_mode_summary">switch between light and dark theme</string>
 
     <!-- ###ABOUT### -->
     <string name="app_name_long" translatable="false">Privacy Friendly Sudoku</string>
diff --git a/app/src/main/res/xml/pref_settings_general.xml b/app/src/main/res/xml/pref_settings_general.xml
index 3102b95..6d59eec 100644
--- a/app/src/main/res/xml/pref_settings_general.xml
+++ b/app/src/main/res/xml/pref_settings_general.xml
@@ -19,6 +19,12 @@
         android:summary="@string/pref_keep_screen_on_summary"
         android:defaultValue="true"/>
 
+        <SwitchPreference android:id="@+id/pref_dark_theme"
+            android:key="pref_dark_mode_setting"
+            android:title="@string/pref_dark_mode"
+            android:summary="@string/pref_dark_mode_summary"
+            android:defaultValue="true"/>
+
         <ListPreference
         android:key="pref_symbols"
         android:title="@string/pref_symbols"