It's one thing to track your heart rate, pulse or other movements with a smart watch or other consumer electronics, researchers say, but quite another to rely on the device to diagnose a disease. It's one thing to track your heart rate, pulse or other movements with a smart watch or other consumer electronics, researchers say, but quite another to rely on the device to diagnose a disease. With sensors that can collect data on body movements, heart rate, blood pressure and other metrics, the list of health trackers that go beyond activity trackers like Fitbits gets longer each year. "There's definitely an explosion of these things," says Dr. Joseph Kvedar, the vice president for connected health at Partners HealthCare in Boston, and an associate professor of dermatology at Harvard Medical School. Some of these devices will lead to a better health care system, Kvedar predicts, with cheaper, more efficient care.