If you use a particular credit or debit card more than others, you can set it as your Apple Pay default on your Apple Watch.
Most of us end up using a specific credit or debit card for making purchases more than the others. Perhaps you get more rewards with that specific card, or something else. Regardless of the reason, you can set a default card on your Apple Watch, just like you can on your iPhone. This way, you don't have to swipe through cards each time looking for the one you want to use. Just hold up your wrist and your default card is automatically used.
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