What are some good two player ipad/iphone games?

My friend and I want a two player game where we can either visit each other or be with each other at the same time but on different phones. We don't want games like chess or tic tac toe. We're really loving high school story at the moment, maybe there are some similar to that? I don't even know if it's possible to be with each other in a game of two different consoles but you never know so I thought I'd ask. ^.^ Thanks!

Bloon TD 5
it has a co-operative mode
its not free on app store here is the free link to download apk http://dl.papktop.com/2014/03/Bloons_TD_5_2_6_1.apk
it has an addictive solo player mode too

Play --|~ Co-Operative --|~ Create or Join Private

Minecraft i guess

Spaceteam

it's local multi-player only (2-8 people in the same room). It's FREE. It's cross-platform (iOS, Android, Kindle Fire). And it's like no other game you've ever played.

I've never had so much fun shouting at my friends, and getting shouted at by them.