The Motorola Atrix 4G from the year 2011 might have been forgotten by most of us, but the device still has active development going on for itself over at the xda forums.
Developer sungkisa over at xda has just posted an alpha build of CM13 for the Atrix 4G. The ROM doesn’t boot at the moment but is a proof-of-development (and hope) for the Atrix 4G to run Android 6.0 Marshmallow.
As of the time of writing this post, the ROM isn’t put up for download. Maybe because of the bugs present, but we’ve good faith sungkisa would be able to get Atrix 4G boot CM13 and get the bugs/issues sorted out.
For further developments, make sure you keep an eye on the this xda thread.
Happy Androiding!
