My Fitbit Air test revealed the flaws of calorie counting with a health tracker - here's why - ZDNET

You should take calorie data with a grain of salt. Here's what I learned after testing the Fitbit Air's heart rate data against a gold standard heart rate monitor.

Nina Raemont/ZDNET
Follow ZDNET: Add us as a preferred source on Google.
ZDNET's key takeaways
<ul><li>I tested the Fitbit Air's heart rate data. </li><li>I compared it against the Polar H10 chest…