The quest for great iPhone apps is ongoing and it gets more difficult each day, as thousands of apps continue to flood Apple’s iOS App Store. Every once in a while we catch wind of a nice addition that is offered for free for a limited time, however, and Wallgram is one such application. Wallgram for the iPhone serves a single purpose: it takes photos from Instagram and turns them into pretty terrific wallpapers. Instagram remains the most popular mobile app on the planet for posting and sharing images, but what happens to all of those great photos once they’re posted? In most cases, they slide down users’ timelines until they’re forgotten forever, but now there’s a way to put