libgdx
https://github.com/libgdx/libgdx
https://github.com/MobiVM/robovm
https://play.google.com/store/apps/details?id=com.nianticproject.ingress&hl=en
https://github.com/libgdx/libgdx/wiki/Project-Setup-Gradle
https://classroom.udacity.com/courses/ud405
https://github.com/udacity/ud405
https://www.udemy.com/libgdx-game-development-masterclass/
https://www.slant.co/versus/1047/1050/~unity_vs_libgdx
https://www.slant.co/versus/1050/1054/~libgdx_vs_cocos2d-x-and-cocos2d-family
http://dariopenic.com/how-to-choose-an-android-game-engine-libgdx-vs-unity/
Web:
https://en.wikipedia.org/wiki/Google_Web_Toolkit