Cyanogen, the popular developer of Android ROMS, has announced official support for Android One devices. The budget handsets now have official support for CM 11 builds based on Android KitKat 4.4 with an official update to Lollipop based CM12 being actively developed.
There have been unofficial ports of CM11 for Android One devices since October 2014, but the ports often had some major bugs, some of which prevented users from using cellular data and the dual-SIM slots. Those issues have since been fixed, but it is always a welcome sign to have official support. This CM11 release should work for all Android One devices, since they all use very similar hardware, Cyanogen has released a unified ROM for all devices.
The Cyanogen team mentioned this in their release:
This release represents a few firsts for us. Not only are these the first Android One devices and first official release of CM for these devices, the Android One device is the first ever officially supported Mediatek device. Mediatek (MTK) devices have been notoriously difficult for the developer community to complete fully functional bring-ups, and this marks a milestone in that effort.