“USCIS: Civics Test Study Tools,” is now available on the iTunes and Google Play app stores. The app helps you prepare for the civics test during the naturalization interview. It also has a game to challenge your civics knowledge, reminder notifications, and review of past tests. You can also switch between English and Spanish.
I tested out the app on my iPhone earlier today and it worked very well. If you are studying for the Naturalization test this is another tool for you. (I still like flash cards the best.)