Brainfish is a Stockfish derivative including an embedded book of 4+ millions of positions. It plays opening moves from its internal book regardless of the GUI setting.
It's expected that Brainfish reaches higher ELO's than the original. I didn't and won't try to verify this but many test topics are available in forums.
Yu can read more about Brainfish in Chessprogramming Wiki
Below binaries are compiled by Aprijal Pasaribu like all recent engine updates of the last month. Bear in mind that the file sizes are big: 22MB compressed and 34MB uncompressed because of the book.
GET Brainfish for 32-bit arm7 pie
GET Brainfish for 64-bit arm8