Frustrating but free
I use this app to control iTunes broadcasting to multiple airport expresses to get synchronized audio throughout the house.
While iTunes itself can be buggy on a PC (Ive learned if you dont sign in it works better) the audio stream is always on point.
As for the app, I have to continually turn wifi off and on or reboot for it to connect, even if using it all afternoon, but when it connects it works great.
Better integration with "Internet Radio" would be helpful.
Bmobrien about
Remote, v4.3.1