If you just bought a brand new iPod touch with a Retina Display or already have an iPhone 4, Square Enix's Chaos Rings [$12.99 / HD] is a game that is highly worth considering with the release of the latest update. Chaos Rings looked great before, and now looks even better with high resolution graphics, UI elements, and text. To sweeten the deal they even added multitasking support for instant switching between battling and whatever other apps you're using.
We liked Chaos Rings enough to award it five stars in our review, and really think it's a game that any fan of turn based RPG's should own. With this latest update, that's especially true if you have a Retina Display device.