Star Walk 2, by Vito Technology, aims to bring constellations to life. Users can point their iOS device at the stars and watch as the app identifies and renders 3d models of the celestial bodies that can be turned and enjoyed from different angles.
Star Walk 2 acts as your guide to the night sky by using your current location to find what stars will be visible. You can also search for specific stars, constellations, or satellites and the app will identify where you have to look to find them. Then there's the Sky Live window, which can show you all the relevant data for your stargazing adventure including sunrise and sunset times, moon phases, and the rise and set times for 4 main planets: Venus, Mercury, Saturn, and Jupiter.
Star Walk 2 also includes functions such as coordinates on each image to make locating your favorite constellation easier, a soft red-mode that preserves your night-vision while using the app, and a Time Machine mode that allows users to see stars in their calculated past and future positions.
You can pick up Star Walk 2 for $2.99 on the App Store.