Part 1: Headset shortcuts
08 September 2010 – Your iPhone comes with a headset which has some nice features on the controller built-into the cord for the right earbud.
Notice that you can adjust the volume by using the plus (+) or minus (-) keys.
Use the Centre button to answer or hang up a phone call.
You can also double-click the Centre button when listening to music to go to the next song and triple-click it to go to the previous song.