What are some good, fun, free games for iPhone 4?

I have Temple Run, but i'm getting tired of it lol any other fun ones? I'm 17 btw so nothing too childish/silly lol

Where's My Water
iSwinging
Tom's Travels
Cube
Where here is a list of FREE game, though it's named iPad games, still many are avaliable for iPhone:
http://www.mahalo.com/free-ipad-games/