For SpriteKit and 2D game development, there are a couple of alternatives. Once you create a game using SpriteKit and if it becomes a hit, you would obviously want to bring it to other platforms as well, such as Android and Windows Phone.

For cross-platform game development, you have Cocos2d and Coco2d-x. With Cocos2d, you can develop games for iOS and Android, simultaneously. You can develop your game in either Objective-C or Swift. Once you've understood development using SpriteKit, you will notice that the syntax is pretty similar, so you will feel right at home.

Industry professionals have used Cocos2d for a very long time to develop stellar games. It is open source and completely free. It has a good community, where you can ask questions to help find answers for your problems, and it is regularly updated. If you are interested, you can access it at http://cocos2d.spritebuilder.com/:

Like Cocos2d, Cocos2d-x is also completely open source and free and supports...