Pi

Fun, easy to learn yet challenging, and a little bit addictive - everything you want from a little game to momentarily take your mind off other matters.
Challenge yourself ... the more correct you can get in a row the higher your score.
Four game modes:
1. Normal - you get 10 lives with each mistake losing a life until they are gone
2. Timed - do your best in two minutes
3. Endless - just keep playing until you decide you've scored enough
4. Crazy - how far can you make it without making a mistake?