Some of the more popular sports wearables don’t just let you track your fitness, they let other people track you.
That’s what Canadian researchers found when they studied fitness-tracking devices from eight manufacturers, along with their companion mobile apps.
All the devices studied except for the Apple Watch transmitted a persistent, unique Bluetooth identifier, allowing them to be tracked by the beacons increasingly being used by retail stores and shopping malls to recognize and profile their customers.
The revealing devices, the Basis Peak, Fitbit Charge HR, Garmin Vivosmart, Jawbone Up 2, Mio Fuse, Withings Pulse O2 and Xiaomi Mi Band, all make it possible for their wearers to be tracked using Bluetooth even when the device is not paired with or connected to a smartphone, the researchers said. Only the Apple device used a feature of the Bluetooth LE standard to generate changing MAC addresses to prevent tracking.