Play or pause music:
click once on the earbuds touch area (both left and right are ok)
Previous:
Double-click the Main Earbud touch area
Next:
Double-click the Vice Earbud touch area
Answer a call:
Click the touch area of the earbud (both left and right are ok)
Rejecting a call:
Long press the touch area of the earbud for 3 seconds (both left and right are ok)