it can also be used to restore and pair the Apple Watch once you restore your new iPhone with the iCloud backup. But if you’re doing a fresh install, or if you’ve missed those steps ...
An Apple Watch that isn't paired to an iPhone is greatly diminished in its capacities. If your smartwatch is not pairing with your smartphone, you'll want to connect it as soon as possible.
Apple creates a backup of your Watch data and stores it in iCloud. If you pair your account with a new Apple Watch, all that data can be transferred over, so you won't lose anything important and ...
Once the reset process is complete, you’ll need to pair your Apple Watch with either the same iPhone or a new one. During this process, you’ll be required to enter your Apple account ...