Casio's canny trek tech

WITH its new WSD-F21HR, Casio has incorporated a heart-rate sensor for the first time to tempt those who have donned Garmins or Fitbits. Like all of Casio's tough watches, the F21HR is still the Hulk of wearables. Garmin Fenix wearers might scoff at it, but dainty Fitbit wearers will be in for a shock.

It's not all for show: the F21HR is MIL-STD-810G compliant, a US military standard issued by the US Department of Defense. So it might be literally bombproof, or, you know, really good at resisting dish soap.

Three shortcut buttons on the side launch maps, all apps and Casio's Activity app respectively. They're large and tactile and are a joy to press.