It's my understanding that you're wanting to use Touch ID on your device instead of having to enter in your Apple ID. Although you won't be able to use Touch ID in place of entering your login information for every Apple ID service, you can definitely use it to make purchases and to unlock your device. I'm happy to provide you with some information on doing this.
Are you using a Touch ID capable iOS device? If so, you'll need to enable Touch ID using the steps here: Use Touch ID on iPhone and iPad . Once it's been set up, follow these steps to use Touch ID to unlock your device and make purchases:
Use Touch ID to unlock your iPhone or make purchases
After you set up Touch ID, you can use Touch ID to unlock your iPhone. Just press the Home button using the finger you registered with Touch ID.
Make purchases with Touch ID
You can use Touch ID instead of your Apple ID password to make purchases in the iTunes Store, App Store, and iBooks Store. Just follow these steps:
- Make sure iTunes & App Store is turned on under Settings > Touch ID & Passcode. If you can't turn it on, you might need to sign in with your Apple ID in Settings > iTunes & App Store.
- Open the iTunes Store, App Store, or iBooks Store.
- Tap something to buy. You'll see a Touch ID prompt.
- To make a purchase, lightly touch the Home button.
Use Touch ID for Apple Pay
With an iPhone 6 or iPhone 6 Plus or later, you can use Touch ID to make Apple Pay purchases in stores, within apps, and on websites in Safari. You can also use Touch ID on your iPhone to complete website purchases from your Mac. If you have an iPad Pro, iPad Air 2 or iPad Mini 3 or later, you can use Touch ID for Apple Pay purchases within apps and on websites in Safari.
If you're using a MacBook Pro that came equipped with a Touch Bar, you'll need to set up Touch ID through System Preferences. You'll find all the steps you need to set it up, enable it to make purchase, and enable it to unlock your MacBook Pro here:
Use Touch ID on MacBook Pro
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