The Tango Remote Music Player performs a neat trick and does it for free: it links any two iOS devices on a wireless network, allowing one to be a music source and the other to be a remote control.
To get going, Tango needs to be on both devices. One device is set to play its on-board music; the other device serves as the remote. In my case, I used my iPhone as a music source while it was plugged into some external speakers. My iPad discovered the iPhone, and I saw playlists, albums, and tracks. I could play anything I wanted from the iPad. Of course it also works the other way, and you can have an iPod touch substituting for the iPad or iPhone.
The only issue I had was that the two devices could not link if Bluetooth was activated. There is an on-sc
