Apps Mobile

Play or pause a song or video

Press the center button once. Press again to resume playback.

Skip to the next song or chapter 

Press the center button twice quickly.

Fast-forward 

Press the center button twice quickly and hold.

Go to the previous song or chapter 

Press the center button three times quickly.

Rewind 

Press the center button three times quickly and hold.

Answer or end a call 

Press the center button once to answer. Press again to end the call.

Decline an incoming call 

Hold down the center button for about two seconds, then let go.
(When you let go, two low beeps confirm that you declined the call.)

Switch to an incoming or on-hold call and put the current call on hold 

Press the center button once. Press again to switch back to the first call.

Switch to an incoming or on-hold call and end the current call 

Hold down the center button for about two seconds, then let go.
(When you let go, two low beeps confirm that you ended the first call.)

Increase volume 

Press the + button.

Decrease volume 

Press the - button

Source: Apple.com