Hardcore fitness junkies need a fitness tracker that can keep up. People new to fitness need a fitness tracker that will whip their ass into shape. The Garmin Forerunner 935 is both, and you don't need to wait until Black Friday to get it for a discount because it's $128 off on Amazon today. At $371.99 even on sale, this beast of a device doesn't come cheap — but it's cheaper than paying for an actual trainer. The 935 sits at the top of the Forerunner hierarchy thanks to highly customizable running and triathlon features. The watch apparently knows the difference between your freestyle runs and runs to beat a PR and tracks accordingly, giving data like ground contact time balance, stride length, and heart rate (even under water). If you start training too hard, it'll let you know to take it easy. Battery life is said to last for a week at a time, nixing the "Bummer, I can't run today because my watch isn't charged" excuse. The biggest drawback is that there's no on-device ...