This wikiHow teaches you how to manage your iTunes and App Store subscriptions using an iPhone.
Steps
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Step 1. Open the "Settings" of the iPhone
This application is usually found on the main screen.
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Step 2. Tap your name at the top of the screen
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Step 3. Tap iTunes and App Store
It is located towards the central part of the menu.
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Step 4. Tap your Apple ID
It is a blue link located at the top of the screen.
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Step 5. Tap View Apple ID
This option is at the top of the menu.
Enter your security code or use Touch ID if prompted
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Step 6. Scroll down and tap Subscriptions
A list will open with all the subscriptions associated with your account.
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Step 7. Tap the subscription you want to manage
A list of options associated with that subscription will appear.
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Step 8. Edit your subscription
The options vary depending on the service or application. You may be given the option to renew it (if it has expired), change your payment plan, or permanently cancel it.