Android app crashes without any exception, when trying to sign in with Google plus

Remove android:noHistory="true" from the <activity> definition of LoginActivity in your manifest. I'm pretty sure that the noHistory setting causes Android to finish the LoginActivity when it starts the Google+ signin activity. Since the activity is already finished, there won't be anything there to call onActivityResult() on. Your app isn't actually crashing, it is just done.

If you want to make sure that the user doesn't BACK into your LoginActivity you will have to solve that problem in another way (override onBackPressed() or something else).