This famous iPad/iPhone game (now available on Android as well) is highly addictive, even if it is silly and vapid. I'm not going to try to explain it here if you don't know anything about it, just know that it's a very simple game to play but actually involves some minimal strategy that makes it pretty fun. I don't play it that much, but I definitely use it to distract my four year old for up to 20-30 minutes at a time. She's now better at it than anyone in the family.View these 20 apps in a one-page list
Also see: The truth about iPad: It's only good for two things
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