And you can use the Dash for tracking basic fitness metrics, but for accurate heart rate measurements, you'll want to stick to a dedicated tracker. (pcmag.com)
But hold down the button on the side of the watch and you enter «workout mode,» and the watch starts taking heart rate measurements continuously. (androidcentral.com)
And while you don't get heart rate measurements, significantly longer battery life seems like a fair trade - off. (pcmag.com)