Authorization through Google?

Question

Google

Guys are interested in one moment, downloaded the source codes (example) of authorization via Google . On one emulator everything works, on the other it just tries to open the account selection window when pressed, but it does not open, a similar situation with a real phone, on 4.2 everything is ok on 5.1 does not work, but the 5.1 emulator works and 4.2 does not ... What could be the matter ?
Update: Release, debug version and Google Authorization?

Answer 1

Yes, and I also write in response to how much a very important thing is, the debug version works on emulators and the release version (does not WORK on 5.1 emulator!).. But on a real phone (redmi note 2 prime) only debug opened ...