The little microphone/switch that bulges out on the right side of the headphones included with the iPhone can do some neat tricks other than answer or hang up a call. When not in a call, you can use this switch to control the iPod functions of the iPhone. It’s a testament to Apple’s designers to implement something simple like this that would be easy to overlook.
When not on a call, if you click the iPhone’s headphone switch once, music will start playing without having to access the iPod features through the screen. The iPhone doesn’t even need to be unlocked for this to work.
Tap the switch once again and the music will pause.
Double-click the switch twice quickly and you will fast forward to the next song.