Ben Drew The Wired Runner 3 REASONS WHY YOU SHOULD (AND 5 REASONS WHY YOU SHOULD NOT) USE YOUR SMARTPHONE INSTEAD OF A GPS WATCH Chances are you have a smartphone in your pocket or bag at this very moment. Smartphones are the 21st century Swiss army knife, part phone, camera, camcorder, game console, and web surfer. And fitness apps – utilizing the smartphone’s GPS sensor – have been firmly creeping into GPS watch territory. Garmin’s Fit app, for example, can track speed,