Like pretty much anything Samsung, I've been left so frustrated with using my Gear S3 to track my heart rate while cycling as it keeps failing which in turn means I have almost no HR data during my regular cycling exercise. In theory, once I select the exercise mode on the watch, the HR monitor goes to continuous measuring, which surely drains the watch battery, however doesn't manage to complete any measurement. If I occasionally try to force a manual measurement, it fails 90% of the time with an error message that says that I should be still and quiet, while I'm out cycling and sweating... Seriously makes me want to smash the watch on the floor.