AirPlay is very cool. You can stream from a Mac to various devices, such as an Apple TV, or to standalone AirPlay-compatible speakers. You can stream from an iOS device to an Apple TV or to standalone AirPlay speakers. But one thing I’d like, which currently isn’t possible, is to stream from an iOS device to a Mac.
The reason for this is, in my case, to play podcasts that are on an app on my iPhone, and not on my Mac, through my Mac and its speakers. There could be many other uses, such as playing someone’s music on your Mac when they’re visiting, or to view an iPad screen on a Mac while playing a game. You can do both of these to an Apple TV, so it shouldn’t be hard to do them to a Mac as well.
I wouldn’t use this feature a lot, but trying out Marco Arment’s new Overcast podcast app, with its great smart speed and voice boost features, I realized that, when I listen to podcasts in my office, I’d rather use that app than iTunes. So I’d like to just stream them to my Mac. The alternative is to connect an AirPort Express to my stereo, but that’s expensive for just streaming occasionally.
But you may even want to stream something from one Mac to another; again, since you can do this to an Apple TV, it should be trivial to do it on a Mac.
Update: I was reminded by a few friends that there are third-party apps that can act as AirPlay receivers on a Mac. I have one, X-Mirage, which I got in an app bundle, but never used. I’ll try it out.