It's generally acknowledged that the iPad 2's cameras are awful. They're horribly low-res, leaving still images looking grainy, lacking in detail and usually flat-out bad. Snapseed is an app that can make taking photos seem worthwhile, or at least fun. And it works wonders with the superior iPhone 4 and 4S snappers.
Snapseed is an intelligent image processing tool that lets you fix photographic blunders, such as over-exposed, off-centre, under-saturated shots, or those in need of cropping. It does a lot more besides, too. You can add a tilt shift effect, selective focusing, plenty of retro camera filters and neat effects that add drama or a grungy look to your shots.
Other than good-quality processing, Snapseed is worth using because of its superb UI. You scroll through effect types at the bottom of the screen and alter the severity and parameters of the filters using touch and multi-touch gestures on the preview image. Those with an iPad 2 and an iPhone 4S are in for a treat - bung your 4S shots onto your tablet and you'll be in photo-fiddling heaven.
A great UI, plenty of filters and customisation options make this photo editing app a must-download for all iOS snappers.