It has ads, but not intrusively. The one irritant that kept me from giving it five stars is that it refuses to take no for an answer about whether you want to be notified about when certain power ups become available, and keeps asking if you want to be notified. However, it won't take that long to get all the power ups to be available, though it will take quite a while to get them fully upgraded. Other than that one personal irritant, great game.