The ability to share makes the app most useful, particularly for photographers who prefer to give the royal treatment to even their Instagrams. When you get something you like, tap the share button in the top right corner. For now, you can only go to services native to the iOS, such as Facebook. To share to Instagram, first save to your camera roll. You can also, of course, send a (non-full-res) image by email or, if it’s set up, by iMessage.