Polar M400 Review Tested by GearLab

Polar no longer makes the M400. We reviewed a deep field of well-designed devices. As smartwatches merge with GPS watches and then absorb activity

Polar M400 GPS Smart Sports Watch with Heart Rate Monitor (Pink) : Sports & Outdoors

Polar M400 Review: Fitness/Sleep Tracker Watch With GPS

Polar M400 GPS Sports Watch without Heart Rate Monitor, Black : : Electronics

Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET

Polar M400 Review

Polar M430 HR Review

Polar M400 Review Tested by GearLab

Polar M400 Review Tested by GearLab

Polar M430 HR Review

Polar M400- Tested and Reviewed!

Polar Pacer Pro GPS Running Watch In-Depth Review

Polar M400 Review - , Running tips