Aps for the iPad (FUN)

I have collected three aps for the iPad which I think are nifty.  The first is Art Authority - 40,000 high quality images from 1000 artists organized by category and artist.  Well worth the $9.99 price.   The images can be downloaded into your photo files incase you want to improve on an old master.   Star Walk - Allows you you see the heavens based on your position and time of day.  It has a night and day view and points of the compass so you can really locate everything in the sky.   We've spent a couple of hours in our back yard locating constellations.  (Note it is even better in a non light pollution sky)  The final one is Art Studio - Which is a simple sketching ap - I am not much of an artist but this one is fun - with a lot of tools.