how do I change from one watch to another when both are currently in use?
Need to move use and data from one phone Thais in use to another
Question marked as
If unpaired from the old iPhone, the Apple Watch will create a backup, which is included in the backup of your old iPhone. Setting up the new iPhone, using the backup of the old one, will also transfer the watch data to your Apple Watch, if paired again to the new iPhone.
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- If you have an Apple Watch and you got a new iPhone, unpair your Apple Watch from your previous iPhone before you set up your new device. Unpairing automatically backs up your Apple Watch so you can restore it after you pair with a new iPhone.
- Make sure that you have a backup of your device.
- Have your Apple ID and password ready.
- Transfer your SIM card from your iPhone, iPad, or eSIM. If your new device needs a different SIM card than what you have, contact your carrier.
- Make sure that you have a backup of your previous device. If you purchased a new iPhone or iPad, you may be eligible for temporary iCloud storage.
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copied from: Transfer data from your previous iOS or iPadOS device to your new iPhone or iPad - Apple Support