Sprite Kit provides a graphics rendering and animation infrastructure that you can use to animate arbitrary textured images, or sprites.
Sprite Kit also provides other functionality that is useful for games, including basic sound playback support and physics simulation. In addition, Xcode provides built-in support for Sprite Kit so that you can create complex special effects and texture atlases directly in Xcode. This combination of framework and tools makes Sprite Kit a good choice for games and other apps that require similar kinds of animation.