Open-source implementation of Microsoft's XNA 4, for Windows, Mac, Linux, Android, and iOS, among others.

MonoGame is an open-source implementation of Microsoft's XNA 4, built on top of DirectX or OpenGL based on platform. It allows developers not only to make new games, but often to port an existing game built with XNA to other platforms, using Xamarin for mobile. Supported platforms are: iOS, Android, Windows (OpenGL & DirectX), Mac OS X, Linux, Windows Store Apps (for Windows 8 and Windows RT), Windows Phone 8/8.1, PlayStation Mobile (currently 2D only), OUYA, and most recently Windows 10 (UAP).