The iPhone's best feature is now easier than ever to use

REUTERS/Stephen Lam

Eddy Cue, Apple's senior vice president of Internet Software and Service, introduces Apple Pay.

Exclusive to the iPhone 6, iPhone 6 Plus, Apple Watch, and soon the new iPhone 6S and 6S Plus phones launching this Friday, Apple Pay lets you make easy and secure contactless payments simply by holding your device to an NFC terminal and authenticating the purchase with your wrist or your finger, thanks to the iPhone's Touch ID fingerprint sensor.

On the Apple Watch, this function couldn't be any easier to find and use. Just double tap the button right below the digital crown, and your available credit, debit, and rewards cards will pop up. Just swipe to the one you want to use, hold it out to the NFC receiver, and you're done!

Prior to last week's iPhone update, using Apple Pay was not as quick or as simple on the iPhone: You'd still need to take your phone out of your pocket, unlock it, find the Passbook app, choose your card, and pay. That's one step too many, compared to the Apple Watch.

But thanks to iOS 9, now you can quickly pull up Apple Pay with a quick double tap of the home button while you're on the lock screen.

Here's how you can easily summon Apple Pay on the iPhone, in GIF form:

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