From the Home screen, tap .
Tap a song in your library to listen to it.
Tap the and checkmark the Show notification option so that the music controller is displayed on the Notifications panel.
Tap Home Key
.
Tap Apps
and tap the application you want to access.
Then, you can listen to music in the background while you access other applications. To control the music, slide the Status Bar down to display the Notifications panel. Here you will see the music controller menu where you can control music playback.