I've been taking pictures with my iPad and it's great. However, some of the pictures that I take end up looking very grainy. Is there an app out there that can clean that up?
Well, the iPad2 cameras are pretty lousy for still images (less than a megapixel - my first digital camera years ago was 2 megapixels) - there is no photo app that will greatly improve these poor images (i.e. GIGO, garbage in garbage out).
I'd suggest using your regular digital camera and then importing the better quality images into the iPad w/ the Photo Connection Kit (a number of threads/posts already available on that topic).
As for a photo app, I am using Photogene HERE - easily crops and resizes images and will do other basic manipulations; of course, there are other apps that will likely be suggested by others - good luck -
I second the Photogene App. Lots of other apps do things similar, but this app has everything in one place. I was able to get rid of a few specialized apps and use Photogene for everything. I don't edit much on my Mac anymore. Plus I love the ability to upload to Facebook or twitter from inside the App. It's a good one.