This wikiHow teaches you how to cancel a subscription charged to your Apple/iTunes account via iPhone.
Step
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Step 1. Open Settings
on iPhone.
You can find it on the home screen.
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Step 2. Touch your name which is at the top
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Step 3. Touch iTunes & App Store
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Step 4. Touch your Apple ID
This blue Apple ID is at the top.
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Step 5. Touch View Apple ID
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Step 6. Type in the passcode or use Touch ID
If your identity has been verified, the device screen will open the Account menu.
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Step 7. Scroll the screen and touch Subscriptions
This will bring up a list of subscriptions to the app and service.
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Step 8. Touch the subscription you want to cancel
Information about the subscription will be displayed.
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Step 9. Touch Cancel Subscription
It's a red button at the bottom of the page. This will bring up a confirmation message.
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Step 10. Touch Confirm
After unsubscribing, the service will no longer charge you. You can still access the features until your subscription limit expires, as indicated on the date.