You can use any Interra debit card, except Interra's HSA debit card. Interra's consumer MasterCard Platinum and Classic credit cards are also available in Apple Pay.
Hold the iPhone or Apple Watch near the payment reader while placing your finger on the Touch ID to complete the payment. You won't need to open an app or even wake the phone display. You will see "Done" and a checkmark on the screen when the payment information has been successfully sent.
The "Find My iPhone" app can suspend all payments in the event of a lost or stolen device.
Apple Pay uses the Near Field Communication (NFC) antenna, the “TouchID” fingerprint scanner and a Secure Element chip built in to iPhone to securely send encrypted payment data to an NFC sensor at the point of sale. Completing a transaction is easy, just hold your iPhone near a contactless reader while holding your finger on Touch ID. For more information, please visit Apple's website.
Apple doesn’t save your transaction information. Apple Pay doesn’t store the details of your transactions so they can’t be tied back to you. Your most recent purchases are kept in Passbook for your convenience, but that’s as far as it goes.
Every time you hand over your credit or debit card to pay, your card number and identity are visible. With Apple Pay, instead of using your actual credit and debit card numbers when you add your card, a unique Device Account Number is assigned, encrypted, and securely stored in the Secure Element, a dedicated chip in iPhone, iPad, and Apple Watch. These numbers are never stored on Apple servers. And when you make a purchase, the Device Account Number, along with a transaction-specific dynamic security code, is used to process your payment. So your actual credit or debit card numbers are never shared by Apple with merchants or transmitted with payment.
No, there is no fee to use Apple Pay.
Apple Pay can be used at participating businesses throughout the United States. Look for the Apple Pay or contactless symbol at your local merchants checkout line. View Apple's website for a current listing of major merchant stores that accept Apple Pay.