In this game you have to solve 50 at first glance simple math problems. But this is actually not so simple. The time for each answer is limited to 10 seconds, and not everyone can give 50 correct answers. After each game, you will always see the number of correct answers, and you can compare your result with other players in the Game Center.
You can also play this game with any person who is nearby. Here you are invited to a short match on 10 questions. After you answer them, pass the smartphone to your opponent. Whoever gives the most correct answers will win.