The best
SkySafari is the best astronomy app out there. I use it with my Celestron GOTO telescope. The WiFi in the scope connects with SkySafari to control the scope. The many features in SkySafari will satisfy a beginner as well as an advanced astronomer. I highly recommend it. Used on an iPhone, mini or full size iPad it awesome.
CarverED about
SkySafari 4 Pro: Professional Telescope Astronomy! Explore Sun, Moon, Mars, Stars, Planets, and Satellites! Go where NASA space missions have not!, v4.5.3