I took the opportunity of a trip to/from Heathrow to check out how ApplePay worked.

Before I left I had to set it up on my iPhone 6. First the card on my iTunes account and then other supported cards - BA Amex and NatWest debit - in my case.

Took a couple of minutes but worked fine.

At the ticket line you have to hold the phone near (not on) the reader and then use your fingerprint to activate payment. This worked OK leaving Finsbury Park, failed on one reader at Heathrow, worked on another at Heathrow and then worked fine on the way home.

My tip - check which finger naturally comes forward when you hold the phone. I had to register my thumb as the 2nd finger is hard to manage whilst holding the phone.

Waiting for the payment to come through to make sure it charged me OK.