RotoView is an app that lets you zoom in super close on your iPhone photos, and then scroll around them by tilting the iPhone itself. It is also a great example of how iOS 7-native design can help an app look great, when otherwise it would very likely look awful.
To be fair, the only evidence I have that the app would be ugly under iOS 6 is the icon, which is a true abomination. But who knows? Maybe the developer would have made a beautiful app with a custom but super-simple UI and then slapped a hideous icon on it. An icon that contains a different name from that of the app. But I doubt it.
The purpose of the app is to let you zoom in way more than you can with the stock photos app, and to be able to move around the zoomed image without constantly flicking to get from one side to the other. Thus you can zoom in up to 30x, and then scroll around by tilting the iPhone. You can also dive into the preferences and fine-tune the tilt sensitivity using such things as “rotation threshold” and “gyroscope frequency,” which actually sounds kind of cool.
The app is free, and can be downloaded right now. Just make sure you half-close your eyes when you look at that icon.