Using Apple Pay, the mobile payments platform the company launched last fall, you could simply lift your Apple-Watch encircled wrist towards an in-store payment terminal.
Without even touching the terminal, the device will recognize it, and make a payment.
If a payment is successful, you would hear an alert and feel a small amount of haptic feedback (a slight vibration).
It's even easier than taking your phone out of your pocket.
Earlier in Apple's presentation, CEO Tim Cook said that the number of locations now accepting Apple Pay has tripled since launch - you can pay with it at 700,000 locations across the US.
You can also pay at 40,000 vending machines without having to "un-crinkle your dollar bills." More than 2,500 banks also work with Apple Pay, up from 6 at launch.
Although Cook's stats about how many locations now accept payments system are interesting, we still don't know the total transaction value going through Apple Pay. Without that, it's hard to get a sense of how many people are actually using it.