android error 12500 - trying to setup google single sign on
If you're hitting this messages and getting error code 12500 then please ensure your emulator supports google play.
You emulator would generally ask you to login to gmail account ...blah blah blah.. if you don't get that, it is almost certain you need to install it. :)
The funny thing is I have emulator with Android 4.4, SDK 19 ad that doesn't work. So I created another emulator with Android 6.0 (Google API) and SDK 23.
Most people don't run into this issue. But if you do, you're sorted now.