How is the Apple Pay transaction authorised?
Once your code or finger are recognised, Apple Pay sends your card provider the key from your Secure Element, plus the amount you're spending and the merchant identifier, which is a double check, unique to that outlet, that ensures only they can receive the payment.
The retailer doesn't need to see your card details, and neither Apple nor your bank gets to find out what you're buying, so either half of the transaction is kept secret from the party who has no need to know about it.
If I lose my Watch or iPhone can someone make purchases?
If you lose Watch or iOS device, putting it into Lost Mode through Find my iPhone suspends the key stored in your Secure Element so nobody can make purchases on your account.
And despite all this, if you still fall foul of a scam - which will almost certainly be a case of human error - the most you can lose in the early days is a paltry £20. That will rise to £30 in the autumn when contactless payment limits not just for Apple Pay, but for all cards, will be boosted by 50%.
To use Apple Pay you will need to set up Apple Pay using the new Wallet app. Here's how to use Apple Wallet app.
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