Mextures are free 2000px x 200px images for adding textures to your iPhone photos. Mextures come from photographer Merek Davis, hence the name: Merek; textures: Mextures!
The textures add the kind of scratchy, dusty, like-leaky effects that you have come to know and love (or hate) in apps like Instagram and the regally awesome Snapseed, only now you can use them yourself, in any app that supports layers.
Mextures will work great in Photoshop Touch, or (seen in the demo video) PhotoForge 2 or something like Blender. You can just set the Mexture layer above the photo layer and drop its transparency until you’re happy, but if you introduce blending modes (scree, multiply, overlay and the like) then things get really powerful.
As I mentioned, Mextures is free, although you’ll have to provide an e-mail address to get them, and you’ll have to download each damn picture individually and save it to your camera roll. Sigh.