'libGDX' is an open-source cross-platform Java game development framework based on OpenGL (ES) that works on Windows, Linux, Mac OS X, Android, iOS and WebGL enabled browsers.
The libGDX project is a cross-platform (Windows, Mac OS X, Linux, Android, BlackBerry, HTML5, and iOS) game development library written in Java with some JNI code. It abstracts away the differences between the different platforms and enables easier development of OpenGL-based games on them.
'libGDX' is an open-source effort, started by Mario Zechner in late 2009/early 2010. In its original form it was an attempt at a rapid prototyping library which avoids the slow development cycle usually encountered when creating pure Android applications. The goal was to be able to work mostly on the desktop, and only deploy to the emulator/a device when absolutely necessary.
'libGDX' now is a multi-backend, cross-platform game development library which is not only targeting Android, but it can also be considered a viable framework for desktop applications (stand-alone, applets, and Web Start).
It includes a wrapper to work directly with box2d (2D physics). And one for bullet (3D physics).
Please note that there's a rich community on the official forum, and an official wiki.
The current stable version is 1.11.0, which was released in May 2022.