Subsplash has Luminance (iTunes Link) for the iPhone, iPod Touch, and iPad in the iTunes App Store for FREE (regularly 99-cents) for a limited time.

Luminance gives you pro photo editing capabilities in a simple and elegant interface. Effortlessly add effects to your photos, choose from many built-in presets, crop the area you want, and copy edits you’ve made from one photo and apply them to multiple photos