I usually enjoy playing, but if you are playing one of the tours, it will sometimes keep the clock running even though you have closed the app while you do something else. Since the whole thing is timed, that is pretty annoying. Again, app hangs and clock keeps running. I guess they are trying to get me to pay for it instead of watching ads. Happened again. Very disappointing. This keeps happening. You can't stop the timer even by leaving the game.