Hi
Apple Watch does not presently have a built-in feature that offers audible or haptic warnings / alerts if it is taken out of Bluetooth range of the paired iPhone. When it becomes disconnected via Bluetooth, if the watch is also unable to connect to a known Wi-Fi network at that time, it will show the Disconnected icon at the top of the watch face:
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If you would like to suggest that Apple considers adding Bluetooth disconnection alerts as a new feature, you can do so here:
www.apple.com/feedback/watc...However, you may find this third-party app of interest:
- Lookout – Security, Backup and Missing Device"Shows you the distance between your iPhone and Apple Watch, and notifies you if they’re about to lose connection."
- "You can now adjust the sensitivity of the Apple Watch connectivity notifications in the Settings section of your Lookout iPhone app."
- itunes.apple.com/us/app/loo...