Cocos2d-x is an open-source and cross platform open source free 2D game engine for mobile game development known for its speed, stability, and easy of use.
License: Open Source
Cocos2d-x is primarily focused on 2D game development with a strong performance and community support, whereas Polycode provides versatility for both 2D and 3D game development with a more user-friendly interface and built-in tools. However, Cocos2d-x may be more challenging for beginners due to its steeper learning curve.