Apple assumes that each device you own is tied to a single user,
i.e., "my iPhone", "my wife's iPhone", "my iPad", "my wife's iPod Touch", etc.
As such, each device can only be set up with
one iCloud account. The information iCloud syncs is meant to be tied to a single user as well,
i.e., "my contacts", "my wife's contacts", "my email", "her reminders, calendars" etc.
However, you can also share an Apple ID for iTunes purchases, so anything purchased from the App Store or iTunes Store can be downloaded to
all devices you own, regardless of that device's user. This is a separate login, distinct from each individual's iCloud account.
In a nutshell, you should have one Apple ID that's used only for purchases, and each individual should have their own separate Apple ID to store their personal information. This individual Apple ID is also their iCloud account. So that's one personal Apple ID (iCloud account) per person. And one iTunes Apple ID (not an iCloud account) that's shared across all your devices.
What you need to do:
For sharing iTunes/App Store purchases across all devices:
1. Open the Settings app, and tap on the "Store" tab, directly under the "Notes" tab.
2. From here, if an Apple ID is already logged in at the bottom, verify this is the Apple ID that you use to make purchases from the iTunes/App Store.
This can be found in the iTunes Store on your Mac/PC. You will see the correct email address in the upper right hand corner at the far right end of the top black bar.
3. Back to your device, if the email address at the bottom of the "Store" settings tab is different, tap on it to log out of that mail and tap again to enter the correct one you found in iTunes.
To keep personal data (contacts etc) separate for each individual:
1. Open the Settings app, and tap on "iCloud". Here, each individual needs to be logged into their own separate iCloud account. Apple doesn't let you log out of your iCloud account for whatever reason, so just hit the Delete Account red button at the bottom.
This will not delete your account from the iCloud servers, it will only delete data on your device, so you don't end up with duplicates, etc. You can log back into this account at any time, and any data will be downloaded back to your device.
2. Now you can create a new iCloud account for each individual. Note that you may keep your original iCloud account and assign a new account to another individual as well. The new iCloud account will be a blank slate however, and personal data (contacts, etc) will either need to be recreated either on the device, or on your Mac/PC under that individual's user account.
So each person will have their own iCloud account for their personal data that will also need to be entered into the iCloud control panel on that person's Mac/PC user account. This will keep personal data separate. Note that everyone can enter the same iTunes Apple ID account in the Mac/PC iTunes application, even though they are logged into a separate ID for iCloud syncing.
Just think of it as, iCloud is for personal data syncing, not purchase syncing.
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ok - so different cloud accounts for the a husband and a wife on their seperate iphones,
but what if they both share a third devise - and ipad for example? Can the ipad be set up to go to different clouds based on who's using the device?
No, Apple has not integrated the idea of multiple user profiles per device. Each device can login to the same account, but you can't log into multiple accounts with each device. You theoretically could delete your iCloud account off your device when you're done using it, then someone can log into theirs while they use it, then delete it again when they're done using it, but that's a huge pain and not practical for what you're wanting.