UPBGE (Uchronia Project Blender Game Engine) is a fork of Blender created by Porteries Tristan (a Blender Game Engine developer) and some of his friends in September 2015.
It's an independant branch, and its aim is to clean up and improve current BGE code, experiment with new features, and implement forgotten features that currently exist but have not been merged with the official Blender trunk.
Its development cycle spans the course of one month: 3 weeks to add new features, and 1 week to fix bugs. Then a new release is made available for download.
Regularly, the UPBGE merges the official Blender new patches, to stay up-to-date with the last Blender evolutions.
The UPBGE team is composed of volunteers; BGE users who are interested in the game engine development, a web developer, and a communication manager.
We hope that new users will join the project, to help us test new features, report bugs, provide feedback and ideas to improve UPBGE (https://github.com/UPBGE/blender/issues), and that new developers will join the team to help us develop shiny new features for the game engine.