This would've been a fun game IF it weren't a pay-to-play. I noticed that I need keys to play and that I'd get a new key once in a while. After using up all the keys it says I can wait some minutes or spend money. I decide to close the app and come back later. Minutes later I get a notif that my Boulder is refuled, but when I come back I still have no keys and... Does that timer still say 4 minutes? I close again, remembering the time, leave it for hours, come back, and the timer has not moved.