Consider authenticating with Apple Pay
. With a fingerprint reader, you can slam your iPhone on the credit card terminal while holding your finger on the Touch ID button, and everything will just work. You're continuously authenticating and beaming credit card data at the same time, which is easy, intuitive, and hard to mess up. According to Craig Federighi's Face Id
demo during the keynote, you now have to open up Apple Pay
first, then aim the phone at your face so Face Id
can work. Only then can you tap against the credit card terminal. That's two extra steps.