The game is really fun, they have a good difficulty curve that lets you learn how the system works then gets into the harder puzzles. There are a lot of ads, but they are only five seconds then you can skip them. The later you get the longer the levels take so they become less common aswell. The game itself is very low pressure since you can undo any move you make at any time. The ads are also much less intrusive because unlike other ads if you happen to misclick the skip button it doesnt assume you meant to open the app store and there is only one skip button, a lot of the annoying tricks many mobile games ads have aren’t here.