/// <summary>
 /// Starts measuring the heart rate.
 /// </summary>
 public void Start()
 {
     _hrm.Start();
 }
 /// <summary>
 /// Starts notification about changes of heart rate value.
 /// </summary>
 public void StartHeartRateMonitor()
 {
     _hrm.Start();
 }
 /// <summary>
 /// Starts notification about changes of heart rate value.
 /// </summary>
 public void StartHeartRateMonitor()
 {
     heartRateMonitor.Start();
 }