Star Walk is 
available for $5 from the Apple App Store, is an 
iPad app
 that helps stargazers spot constellations and planets from where they 
are standing. It makes discovering more than 9,000 stars, planets, 
constellations, and messiers beautiful and easy using OpenGL ES 2.0 to 
create stunning 3D graphics delivered at 30 fps. 
Star Walk
 uses the accelerometer, compass, and Core Location frameworks to 
accurately determine orientation, bearing, and location to enable 
viewing of the night sky as it appears from your location. 
Hold the iPad up to the sky and see the stars in that position. Pan the 
iPad across the sky and see the stars enter the iPad and display their 
names and other information.
It seems like magic, it is hard to believe it is possible. The 
aesthetics of this app are of the very highest caliber. It's a top notch
 application that will impress and educate.