Cell Phone/Tablet Astronomy Apps

What's your favorite Astronomy App(s)? Why not share this information with your friends? We are going to publish a list of favorite Astronomy Apps on this Blog and would like your input. My favorites are: Heavens-Above, MoonPhasePro, dateandtime.com, and ISSTracker. Send you favorites (Apple or Android) to: Skywatcherhost@gmail.com