Works with Cocos2D, the standard Objective-C game engine for mobile.
Open-source, MIT licence, commercially friendly, compatible with both closed and open source apps & games.
Build your apps & games natively at top speed in Objective-C for iOS, Mac, and Android (via SpriteBuilder Android Plugin).
Has a clean API, great documentation, an active, friendly community, and comes with plenty of examples and tutorials.
Easy to extend; works with any third-party library and all of Apple’s native APIs.