No surprise that an app. for Apple's iPad can easily assist aviators.
I have seen one app. that works with our GPS locations to support astronomy. Holding the iPad up to the sky — anywhere — reveals constellations and planets. Tapping one of a constellation's stars or an identified planet allows the viewer to get information about it. Awesome and entertaining (and educational).
The Kindle app. for iPad will obviate my need for a reading light while in bed at night. Yep… I plan to purchase the iPad 2 once it gets released.