Just last week I wrote about Wayland's Weston now running on Android after weeks of work by Pekka Paalanen, an employee of Collabora. Yesterday an email hit the Wayland development list with the title of "Add Android backend" as part of a set of five patches from Pekka.
Below is the patch description for the Weston Android back-end.
The Android backend provides basic EGL/GLES2 graphics, where everything is always composited. Overlays are not used. Input is stubbed, therefore there is no input yet.
This adds the first C++ source file into Weston compositor. The Android gralloc and fb HAL glue code to the Android EGL library is in C++, and there is no way to access it from plain C. We have a simple wrapper to the required C++ class API. Android forces the C++ file name extension to .cpp.
The android backend is compiled by default. However, all Android specific calls are protected with #ifdef ANDROID, so it will build also without Android headers. The binary produced without the Android build system is useless, but allows build-testing generic Weston changes. Therefore the android backend is not installed.