How to restrict access with parental controls for iPhone or iPadKeep your child from making changes to your account and more on iPhone and iPad.
Parental Controls, also known as Restrictions, let you manage which features, apps, and content your kids can and can't access on your iPhone or iPad. This includes preventing any changes being made to your email, contacts, and calendar accounts, to cellular data usage or background app refresh, and to volume limits. Whether you're worried your young child will accidentally delete your accounts, or your pre-teen might try to add a new account, you can quickly and easily lock it all in Settings.
How to block the ability to make changes to accounts, cellular data usage, background app refresh, and volume limits on iPhone and iPad
Launch the Settings app on your iPhone or iPad.
Tap on General.
Tap on Restrictions.
Tap on Enable Restrictions at the top if they aren't already. If they are, skip to step 7.
Type a 4-digit password that only you will know. Your child should never know this password.
Typ...
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How to restrict access with parental controls for iPhone or iPad