While the game is fun, if you change phones any progress, trophies, and earned prizes do not transfer. I had done over 450 puzzles, had several trophies and over 80 earned hints. I contacted the developer and asked what happened and was told they didn't do that but maybe on the next update. No apology, no offer of hints for the inconvenience, nothing. I'm posting this so that others know before they invest time and effort in this game.