This article explains how to sign out of your Apple ID on an iPhone. This account is used by many services on your phone (for example, to log into iCloud, iMessage, FaceTime, iTunes, and others) that may no longer be available once you log out.
Steps
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Step 1. Open Settings
The icon is represented by gray gears and should be on the Home screen.
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Step 2. Select iCloud
It is located in the fourth section of the "Settings" menu.
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Step 3. Select Exit
This option is located at the end of the menu.
The first option in the iCloud menu should be your Apple ID (with name and email). If not, the phone is not currently linked to an Apple ID, as no login has been made
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