I’ve been playing around a little bit with how best to negotiate having more than one iOS user in the house. In the past we’ve had each iPhone and the iPad all using the same AppleID. This lets me buy an app on my iPhone and then load it to my wife’s, too. The problem I’ve started to notice is that there are some services that are better if the device is tied to a particular person. You want to have separate Game Center accounts, for example. The new messaging service in iOS 5 will mean you want to have individual accounts.
Here’s the setup I’ve tested:
- My iPhone with my AppleID syncing with my MacBook.
- I have an iPad with my wife’s AppleID syncing with my MacBook.
- My wife’s iPhone with her AppleID syncing with her account on the MacBook (a different iTunes library).
Here’s what I’ve found:
- Both iTunes libraries are authorized for both our AppleIDs, so either can play videos and run apps purchased by either account. All devices synced to either library can play media bought from either account.
- App upgrades don’t seem to work as well. If device A is signed into account A (via Settings → Store), it can run apps bought by device B, but you get an error if you try to update that app on the device. You can sign out in Settings, sign back in under the other account, update the app, and sign back out (and in), but that’s a lot of tapping around.
- Home Sharing will copy new purchases between the two iTunes accounts if iTunes is running under both logins at the same time, but it doesn’t seem to copy over updated apps. That is, the first time User A buys an app (or video or song), Home Sharing will copy it into User B’s iTunes automatically (if you set it to do that). But if there’s an update to the app that User A downloads, Home Sharing doesn’t automatically grab that update. The Apps area of iTunes will show that there’s an update available, but User B will be prompted to enter User A’s password to download those updates. (She’ll then be logged into User A’s iTunes account in the store and should sign out and back in and could accidentally make purchases under his account. This may or may not matter, but it’s worth noting that it’s not a one-time authorization, it’s a logging-in.)
In summary, if you have multiple users who have reasons to use their own AppleIDs (and I think iMessage will be a reason), it’s by far easiest to sync them all to one single iTunes library. You shouldn’t have any problems doing this as long as you try to have only one account buy all the apps. Upgrades can be done from inside iTunes and will be synced out to the other devices from there.
Edit: I should also add, you can be signed in as different AppleIDs in different places in iOS. You can have one AppleID entered for Game Center and another in Settings → Store, for example, so you can easily use one family account for app and media buying and then have different ones for iMessaging and Game Center.