TL;DR: Check the companion app's connected-account and data-sharing settings for third-party apps you don't recognize having access to health or location data synced from the watch. Review the data-sharing and connected-apps settings in the watch's companion app, revoke access for anything you don't use, and keep both the watch's firmware and companion app updated to patch known vulnerabilities.
Check the companion app's connected-account and data-sharing settings for third-party apps you don't recognize having access to health or location data synced from the watch.
What Usually Causes This
Smartwatches sync a large amount of data (location, heart rate, activity) to a companion app by default, and that app's own privacy settings often allow broad third-party data sharing unless manually restricted.
What to Do About It
Review the data-sharing and connected-apps settings in the watch's companion app, revoke access for anything you don't use, and keep both the watch's firmware and companion app updated to patch known vulnerabilities.
If this looks similar to something else you've seen, it's worth reading AirTag Stalking: How to Check If You're Being Tracked.
This pattern shows up elsewhere too — see How to Tell If Your Bluetooth Devices Are Being Tracked.
Frequently Asked Questions
What are the real warning signs?
Check the companion app's connected-account and data-sharing settings for third-party apps you don't recognize having access to health or location data synced from the watch.
What usually causes this?
Smartwatches sync a large amount of data (location, heart rate, activity) to a companion app by default, and that app's own privacy settings often allow broad third-party data sharing unless manually restricted.
What should I do about it?
Review the data-sharing and connected-apps settings in the watch's companion app, revoke access for anything you don't use, and keep both the watch's firmware and companion app updated to patch known vulnerabilities.
Should I be worried if I only see one sign?
One sign alone (like a slower device) is usually not cause for alarm — most single symptoms have mundane explanations. Multiple signs together, especially unexpected data usage or unfamiliar apps, are worth investigating.