Heart rate is a key metric for tracking health and fitness, and thanks to smartwatches and fitness trackers with built-in sensors, monitoring it is easier than ever. As Android Authority's wearables expert, I've tested countless heart rate monitors over the years, from chest straps to wrist-based trackers, evaluating everything from accuracy to comfort. Some offer focused, high-quality heart rate data, while others deliver more versatile, all-in-one tracking. Below are my top recommendations.