if you want a good art program for the ipad, i'd totally recommend ProCreate. it doesn't have a free version, but it's got tons of brushes, a blending tool, a canvas size adjuster, a full color wheel, and the option to save as a PNG!! it's also got a fairly easy interface to learn, but maybe that's just my point of view. (shrugging) it's $5.99 on the app store, if you've got a few bucks to spare!