Stargazing is a hobby that requires not only time but also considerable knowledge – if just looking at shiny stars isn't enough and you also need to understand what exactly it is that you're seeing. Luckily, you can cut down on the learning front with Star Walk, an app that tells you everything you need to know about the constellations, moon phases, meteor showers and other celestial events above you. You can either see details of the sky on your phone screen or use your phone's camera for an augmented reality look.