"Unfortunately, Google App has stopped". Locked out of my phone! Please help! My phone started popping up with "Unfortunately, Google App has stopped." notification non stop. The keyboard wouldn't come up on my phone. I decided to restart my phone, which I guess was a bad idea because now I'm stuck on the lock screen. The keyboard won't come up, so I can't type in my password to get into the phone. I've tried restarting, taking the battery out, leaving it off for a while. Nothing has worked. I tried going into Safe Mode but the keyboard still won't come up. I also tried going into recovery mode and clearing the cache, that didn't help either. I would really like to avoid a factory reset. Help??
I have a possible solution. But I don't think it works most of the time.

When you are at the lock screen and your keyboard doesn't pop-up, connect the phone to the charger or your laptop/desktop. It resets the processes and your phone will come back to normal. Disconnect the cable if connected previously. After the lock-screen is opened, take a gap of 20 - 30 seconds and connect it and try opening it.

This is an old regulation for many android phones and worked a lot of times in my case with Sony Xperia SP C5302. Hope it works in your case also.