Simplify Media connects your iPhone to your friends' music libraries.
One of the features of iTunes that comes in handy on large networks is the ability to share music libraries with other iTunes users. Simplify Media extended this functionality in iTunes back in 2007 by allowing sharing with up to 30 other people outside of the local network. Its new mobile app enables streaming over Wi-Fi or over the cellular network, to allow even more portable access to friends’ music libraries.
Lets face it, you have way more than 16GB of music at home. You've set up a Smart playlist to shuffle your songs, but when you got a hankering to listen to Minor Threat and the closest thing you got on your iPhone at the moment is Avril Lavigne. Well, it's a pain.