Find In Mind

This is less one game than a rotating set of small brain teasers, with each level built around a different skill, spotting a difference, remembering a sequence, working out a logic step, rather than repeating the same mechanic over and over. Coins earned along the way buy items that help on harder stages, which matters once you're chasing three stars instead of just clearing the level. With thousands of levels stacked up, the variety is really the point rather than any one puzzle type.