Use Apple Pay in apps and on the web on iPhone
You can make purchases using Apple Pay in apps, in App Clips, and on the web using Safari wherever you see the Apple Pay button. (Available in certain countries and regions; see Countries and regions that support Apple Pay.)
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Pay in an app, in an App Clip, or on the web
During checkout, tap the Apple Pay button.
Review the payment information and set any of the following:
Credit card
Billing and shipping addresses
Contact information
Tip: If you subscribe to iCloud+, you can use Hide My Email to keep your real email address private.
Frequency and amount of recurring payments (if available)
Complete the payment:
On an iPhone with Face ID: Double-click the side button, then glance at iPhone to authenticate with Face ID, or enter your passcode.
On an iPhone with Touch ID: Authenticate with Touch ID or enter your passcode.
Change your default shipping and contact information
Go to Settings
> Wallet & Apple Pay.
Set any of the following:
Shipping address
Email
Phone