MacSailing.net

AirPlay is the new feature coming to iOS 4.2 for iPhone/iPad. It allows one to redirect any audio or video on the iPhone/iPad to a different place (i.e. like an Apple TV, an Airport Express w/connected speakers). It is accessed by double tapping the home button and selecting the AirPlay button in the task bar (you will have to scroll right to access).

One could use AirPlay to redirect the iNavX anchor alarm audio or music from iTunes.

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I think you are confusing AirPrint with AirPlay..

http://www.macsailing.net/fbb/showtopic.php?tid/1312/