It's a boom time for fitness trackers, and there are more choices to suit every wallet.

While smartwatches have certainly taken over, activity bands and bracelet style wearables are still immensely popular. And for good reason – they're suited to smaller wrists, generally less techy and easier to use. So what can a fitness tracker do? Think step counting, measuring calorie burn, heart rate monitoring, detailed sleep tracking, swimming, stress tracking, sports, and workout modes. And some of the best fitness trackers even pack in GPS.