The description of the engine taken from its homepage:
"Corchess is a clone of Stockfish source code maintained by Ivan Ivec for better performance on long time controls, trying at least partially to fill the gap between regular tests and demands of correspondence players.
The idea is to improve the following scalability of Stockfish 8.
Starting from version b3, all patches are first tested at 200+2 time control (1 thread, 64 MB hash, 1000-2000 games) and then tested with 10000 games at 40+0.4 time control (1 thread, 16 MB hash). To minimize statistical errors, all patches will be tested against Stockfish rather than against previous version."
Thanks to Alexei for porting it to Android:
GET Corchess 1.1.20170408.ACH for arm7
In case of trouble downloading from your PC, use your mobile device or refer to THIS POST.