Here's what happened when I wore 10 fitness trackers at once

We went to a local electronics store and bought a bunch of devices, from brands like Fitbit, Garmin, Polar, Misfit, Jawbone and Withings. We borrowed one Fitbit and two Apple Watches from colleagues. We ran the devices through three specific tests: counting steps, heart rate and total distance. The results were all over the place.
Thu, May 26 201610:00 AM EDT