Gravity Challenge is a 2d game that I developed for my degree thesis. In the game the aim of the player is to finish the track in as short a time without breaking his moto. There is also a modality “challenge” where users can challenge their friends online asynchronously in a particular track.
I used cocos2d as game framework, box2d as physic framework, the game is written mainly in Objective-C (and some parts in C++).

This is a short video that show the gameplay of Gravity Challenge