MOS is described as 'Lightweight cross platform game engine/library, written in modern C++. Some of the included functionality is: 3D mesh rendering, physically based material model, global illumination, particle rendering, text rendering, collision detection, 3D audio playback and asset' and is a game development tool in the development category. There are more than 10 alternatives to MOS for a variety of platforms, including Windows, Linux, Mac, Android and iPhone apps. The best MOS alternative is Torque 3D, which is both free and Open Source. Other great apps like MOS are OGRE, Pygame, Grit Game Engine and irrlicht.