the author of this app says:
This chess program has 30 levels of play to choose from. You have the ability to save and load games in standard PGN files, which means you can interchange games with other chess software. This game even offers move suggestions and allows you to take back your last move.
Version 1.1 now features the ability for the computer to "think" while you play your move, thus saving time. A tutor option will also warn you if a blunder or weak move is played, and give you the option of take-back.