Great starting off, but gets pretty cheap later on. The later update addressed most of the feelings you were locked into constant micro-transactions to progress, but its still there in later levels, specifically the time limits. I have no problem paying to remove ads or unlock additional features, but not when levels just become cheap to force you to buy continues to progress. Time-limits counting down while menus load and enemies act in a 2-min level just makes you want to quit. The lack of leaderboards is also a pretty glaring omission.