I have an iPhone and two iPads. One of the ipads uses the same Apple ID as the iPhone, and that works well. I want the other iPad to also share that Apple ID. When I try to change the Apple ID to the one used on my iPhone, it says "already in use ... choose another." How can I make this work?
iPad, iOS 9
It sounds like you are trying to change your Apple ID email address instead of signing in with your other Apple account. An email address is linked to a single and specific account. You need to instead sign out of the one account and sign in with the other. Note that if you do not want content merged between the two accounts you need to pay close attention to notices it presents you with when doing this.
Read this document to learn how to sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac --> Sign out of iCloud on your iPhone, iPad, Apple TV, or Mac - Apple Support
For an Apple mobile device:
1. Go to Settings, then tap your name.
2. Scroll down to the bottom.
3. Tap Sign Out.
4. Enter your Apple ID password and tap Turn Off. (Read this if you If you forgot your Apple ID password - Apple Support )
5. Turn on the data that you want to keep a copy of on your device.
6. Tap Sign Out.
7. Tap Sign Out again to confirm that you want to sign out of iCloud.
Also of possible relevance:
Turn off Find My on your iPhone or other devices - Apple Support
Read this support article to learn how to sign in with your Apple ID on various kinds of devices --> Sign in with your Apple ID - Apple Support
For an Apple Mobile device:
1. Open the Settings app.
2. Tap Sign in to your [device].
3. Enter your Apple ID and password.
4. If prompted, enter the six-digit verification code sent to your trusted device or phone number and complete sign in.
If another Apple ID is signed in you may need to enter the password for that ID to sign out of that ID first.
It sounds like you are trying to change your Apple ID email address instead of signing in with your other Apple account. An email address is linked to a single and specific account. You need to instead sign out of the one account and sign in with the other. Note that if you do not want content merged between the two accounts you need to pay close attention to notices it presents you with when doing this.
Read this document to learn how to sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac --> Sign out of iCloud on your iPhone, iPad, Apple TV, or Mac - Apple Support
For an Apple mobile device:
1. Go to Settings, then tap your name.
2. Scroll down to the bottom.
3. Tap Sign Out.
4. Enter your Apple ID password and tap Turn Off. (Read this if you If you forgot your Apple ID password - Apple Support )
5. Turn on the data that you want to keep a copy of on your device.
6. Tap Sign Out.
7. Tap Sign Out again to confirm that you want to sign out of iCloud.
Also of possible relevance:
Turn off Find My on your iPhone or other devices - Apple Support
Read this support article to learn how to sign in with your Apple ID on various kinds of devices --> Sign in with your Apple ID - Apple Support
For an Apple Mobile device:
1. Open the Settings app.
2. Tap Sign in to your [device].
3. Enter your Apple ID and password.
4. If prompted, enter the six-digit verification code sent to your trusted device or phone number and complete sign in.
If another Apple ID is signed in you may need to enter the password for that ID to sign out of that ID first.
Apple ID on two iPads
