If you're using Apple Pay on your iPhone or iPad, you may have already realized that you can add multiple cards that you can toggle between when making purchases. Even better yet, for times when you don't want to launch Passbook at all, or just to make the process even quicker, you can choose a default payment card. That means unless you manually choose a different card for a specific transaction, the default will be used for every transaction you make, both online and in-store.
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