I remember doubleTwist as an iTunes alternative from back in the day, but it's apparently morphed into an Android application and promises to bring many of the standard iTunes and iPod music features to the Android platform. Now the app has added yet another trick to its arsenal: doubleTwist now features support for AirPlay so that users can stream music, videos or photos from an Android phone to an Apple TV or any other AirPlay compatible devices. The app itself is free on the Android marketplace, but you'll need the AirSync add-on, which sells for US$4.99.
Of course, those of us running just iOS devices don't have to worry about hooking AirPlay up (that's kind of what it's for), but if you have an Android phone and want to sync your media across devices, doubleTwist is happy to help. Engadget also points out that another Android app called Twonky Mobile also offers AirPlay integration, though it doesn't have the rest of doubleTwist's robust feature set.