I had a really bad feeling because in one of the games I played on my phone I was practically winning, I just had to attack my opponent, but the game crashed right when I was about to attack.
After a while of complaining about Gods Unchained on reddits, I was given a secret tip to “fix” these errors and crashes on mobile.
As soon as you start to get stuck, just go to the “Home screen” on your phone, then wait a few seconds and come back and everything will be fine. Don't worry about the time, when you do this, it's as if you've been disconnected, so you have 60 seconds to return or you'll lose your turn.