The Apple ID is the center of the Apple universe, particularly for purchases and iCloud synchronization. That becomes a tricky issue whenever a single person's Apple ID is used by multiple people, whether spouses, partners, or roommates, or—as is quite common—by children before a parent grants them their own Apple ID.
It's easy enough to create an Apple ID for a child. If they're under 13, you have to have Family Sharing enabled and you create the account as part of that system. From 13 on up, you can still use Family Sharing, or you and they can create a freestanding account. (That cutoff age is different in some countries.)
You can then use Settings > account name in iOS and iPadOS, the iCloud preference pane in macOS through Mojave, or the Apple ID preference pane in Catalina to change the Apple ID associated with the device or macOS account.
However, not all data may make the transition. Games in particular can be tricky in iOS and iPadOS, if your kid wants to retain progress. Depending on the game, they might wind up in one of several different scenarios:
The game relies on Game Center, and Game Center is associated on each device or account with an Apple ID. Changing that may lose progress, but it will certainly lose rankings and all the connections with other people in it for multi-person gaming and competitions (if you allowed that).
For games played across devices or platforms, the developer stored data in iCloud, which is also tied to an Apple ID.
The game had in-app purchases. Even if you rely on Family Sharing and the game app is available (as most are) for purchase sharing across the family, in-app purchases are not included with shared apps. You will at least have to buy the in-app purchases again.
In the best cases, the game's progress is either entirely stored on the device, or it’s connected to an account system managed by the app maker or a third-party game system online. (With a third-party account, of course you would have had to set up that login for your child; if you’re sharing an account there, you have the same issue of untangling progress.)
In the former case, you probably cannot delete the app and reinstall it as a Family Sharing shared app, because deleting the app will destroy all stored data. You can keep the app downloaded or purchased using your ID in place, but your kid may be prompted at times for the password to your Apple ID, particularly when updates appear.
In the latter case, the very best one, you can delete and reinstall the app, then log in with the account for the game developer. That will then restore progress or other features just as if you had logged in from another device or via the web, where available.
This Mac 911 article is in response to a question submitted by Macworld reader Stanley.
Ask Mac 911
We’ve compiled a list of the questions we get asked most frequently along with answers and links to columns: read our super FAQ to see if your question is covered. If not, we're always looking for new problems to solve! Email yours to firstname.lastname@example.org including screen captures as appropriate, and whether you want your full name used. Not every question will be answered, we don’t reply to email, and we cannot provide direct troubleshooting advice.