Garmin’s Fenix GPS smartwatches aren’t for the faint-hearted. If you just want to wear something that’ll make you feel healthy and everybody else think you run marathons for fun, there’s absolutely no need to fork out £850 for a Fenix 6 Pro Solar. However, if you actually do run 26.2 miles for fun, its new Power Glass uses the sun’s rays to add up to 72 hours to its 21-day battery life, while PacePro tech adapts to elevation on your route to keep you running at the right pace. To make the most of its new sun-supping skills, the round display is 36% larger than its predecessor. It’ll track multiple sports, not just running, use your heart rate to work out Pulse Ox, and deliver notifications from your phone to your wrist. Live somewhere where the sun never shines? The solar-less editions start at a more affordable £530.