AirView

The AirView is a free iPhone app from AirPlay. This app transforms your iOS device into an AirPlay video receiver. You can use the AirView application to watch AirPlay video streams from another iOS device (iPhone, iPod Touch or iPad running iOS 4.2) on the same local network as yours, or from iTunes.

All you have to do is launch AirView, tap the AirPlay icon on the YouTube media player from another supported device, and the video starts playing on AirView. The AirPlay button allows you to choose the client device. This works with videos played in iTunes on a Mac or PC too. The AirView app does not support photos.