![Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET](https://www.cnet.com/a/img/resize/2b801963ea3df437c926c8204a277e93e199bc1a/hub/2014/11/18/d4058596-e577-4eda-8536-a2398b2f808e/polar-m400-product-photos-19.jpg?auto=webp&fit=crop&height=360&width=640)
Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
![Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET](https://www.cnet.com/a/img/resize/c7c441cb6aaaaaab2c03f0c0e833b6fdf744cccf/hub/2014/11/20/2b4eef50-b6e6-4a90-a19e-755b53f16f30/polarm400.jpg?auto=webp&fit=cover&height=482&width=856)
Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
Polar - #TeamPolar, we've got a bunch of updates for you: - M400 and V800 firmware - Flow web service - Flow app iOS And the icing on the cake: Flow app
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