The waterproof watch includes built-in GPS, a six-LED heart rate sensor and better indoor activity tracking. The new accelerometer and algorithms have also been tweaked for more accurate indoor sessions.
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We're big fans of Polar's heart rate chest straps, most notably the Polar H7, which has for a while been one of our "gold standard" devices for accuracy. So it will be interesting to see whether the new wrist sensor can measure up. It certainly bests the M200's two-LED HR sensor on paper, and should make for a more serious running companion.
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Polar USA President Tom Fowler insists accuracy is top-notch. When we interrogated this a tad further, he said he had seen a difference of 1-2bpm at most when using a chest strap against the M430's HR sensor in testing. We haven't been able to try it ourselves yet, but we found the heart rate monitor on the Polar M600 Android Wear watch to be great in our review, so expectations are obviously high.
Fowler told Wareable that he thinks the M430 "will appeal to a broader audience" than the M400. Since reviewing that watch, the company has made big strides with its Flow and Smart Coaching, and you'll have that on hand to guide you through sessions and give post-performance feedback. You'll also be able to upload your own training plans to the watch.
Polar reckons you'll get about 30 hours of life from the 240mAh battery when using the low-powered GPS, and up to 20 days with moderate use. You'll probably be able to squeeze out a fair bit more if you're giving the workouts a rest and just making use of the sleep tracking.
We wrapped the new watch around our wrist for just a few minutes, and it felt as snug and comfortable as the M400, however another difference with the M430 is that it comes with a perforated strap to let the skin breathe better and avoid any discomfort from a sweaty wrist.
The M430 is also changing the way notifications work. You'll still see them on the screen, but you'll now get a vibration alert rather than a tone. Fowler told us that this was so you're more likely to notice them during a run.
The Polar M430 will be available in three colours - orange, white and dark grey - and ships in May for $229. Pre-orders will be open soon. We'll be getting our hands on a sample soon to see if the new Polar watch is up to the task.