Pixel art has hit something of a renaissance, used in everything from retro art to computer games. Rizer's Pixaki turns your iPad into a full-on pixel art studio, loaded with a ton of features you'd expect from a proper professional art app. Don't let the retro look fool you, though: Pixaki comes with drawing, shape, selection and palette tools, and support for up to 50 layers, with the option to import images and photos as layers for you to draw over, as well as animation features. Images can be exported to a variety of formats, such as PSDs, GIFs, PNGs, sprite sheets and more.