I looks like Facebook is working on a massive photo sharing application for the iPhone. TechCrunch got their hands on documents, photos, and screenshots outlining the features: location elements, likes, comments, multi-picture mode, filters, multi-user albums, face-tagging, and more. They say it's almost like a mashup of Instagram, Color, Path, and Path's upcoming With. And though it might seem to be a reaction to iOS 5's new Twitter integration, they say it's been in development for a while now.