How Apple Pay works
What happens behind the scenes when you add your credit card to Apple Pay, and when you pay using Apple Pay through your iPhone device.
Nice in depth dive on how Apple Pay works.
Update: Apparently this is all wrong. See below.
This isn’t how it works, iOS doesn’t give the device card number to the eCommerce server, iOS literally doesn’t know it. I think there’s a WWDC video where we run through it. https://t.co/kpVckU08N1— Nick Shearer (@nickjshearer) September 22, 2022