Chess, with 9 different levels, so you can test your levels exactly.
For each level, you have to win 3 consecutive times to pass. After all levels passed, you are the same level as professional Chess player.
For the buttons, they are: 1) rate, to rate the app in app store 2) mail, to invite friends to play this app 3) restart, to surrender and restart a new game
This is a professional test, no undo! Welcome any advice and suggestions.