The Music Player Framework in iPhone

Getting started: MPMusicPlayerController

You need to add MediaPlayer.framework to your target in Xcode and #import <MediaPlayer/MediaPlayer.h>. To control music playback, we use an instance of MPMusicPlayerController. There are two types of music players. The iPodMusicPlayer is a reference to the music player instance used by the iPod app. Any settings you change, such as the shuffle or repeat modes, will be changed in the iPod app, too. If the iPod is playing when your application starts, the music will continue playing and you can access the current song and skip back and forward through the currently active playlist. When your app quits, the music will continue playing. I imagine this mode is very handy for most utility apps that try to improve your music listening experience by interacting with the iPod.
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