diff --git a/res/xml/lab_preferences.xml b/res/xml/lab_preferences.xml
index 3320cee..a3de6ca 100644
--- a/res/xml/lab_preferences.xml
+++ b/res/xml/lab_preferences.xml
@@ -26,4 +26,9 @@
         android:defaultValue="false"
         android:title="@string/pref_lab_fullscreen"
         android:summary="@string/pref_lab_fullscreen_summary" />
+    <CheckBoxPreference
+        android:key="inverted"
+        android:defaultValue="false"
+        android:title="@string/pref_lab_inverted"
+        android:summary="@string/pref_lab_inverted_summary" />
 </PreferenceScreen>