Sync an Apple Watch (GPS + Cellular) to a new iPhone with NumberSync

If you’ve upgraded to a new iPhone, make sure to complete the activation process before syncing it to your Apple Watch Series 3 or Series 4.

1. Go to the Watch app on your iPhone and follow the prompts to start pairing.
2. Select Set up Cellular. Syncing to another iPhone with a different mobile number? Select OK when you see a message asking if you want to sync with another phone. (If you upgraded to a new iPhone you won’t see this message.)
3. Enter the Emergency 911 address. This is the address where you’ll use the watch most often. 
4. Make sure to check the box and read the Important Information for NumberSync on the 911 screen. 
5. Select Ok on the Sync requested screen when you see a message that NumberSync should be available shortly. 
6. Follow the prompts to finish setting up your watch.

Good to know: When you place a 911 call using your watch, the call goes over the mobile network when possible. If a mobile network isn’t available, emergency services use device location data from nearby Wi-Fi networks to locate you. If that data isn’t available, they’ll come to the address you provide.

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