Meet Approach X40 from Garmin: an activity tracker for golfers that measures your heart rate and offers you with golf data for more than 40k courses. The device is slim and lightweight. It shows you distances to the front, middle and back of each green and can serve as an automatic shot tracker. With smart notifications, you can stay connected.
The Approach X40 tracker is compatible with the TruSwing club sensor. Garmin has more info on the product.