PlanetFinder application is extremely simple to use. It'll automatically pick up your location and compute the planetary positions relative to your device.

In the augmented reality view just point your device toward the sky and discover the celestials that are in your sight.

In the compass layout you're in the middle and the celestial bodies (planets, stars, galaxies and more) are plotted around you.

Check out this introduction on how to use the astronomy compass:

PlanetFinder introduction video