To read data from the gyroscope you need to make some modifications in the view model. You start with creating a field representing a gyroscope:

private Gyroscope m_gyroscope;

An initialization of the gyroscope is very similar to the accelerometer setup. You check whether the gyroscope sensor is supported and then create a new instance of the Gyroscope class, handle the CurrentValueChanged event, and start using the gyroscope. In case of any exception, you just set the value of m_gyroscope to null. The process of initialization is presented in the following code:

public void OnNavigatedTo(NavigationEventArgs e)
{ (...)
  if (Gyroscope.IsSupported)
  {
    try
    {
      this.m_gyroscope = new Gyroscope();
      this.m_gyroscope.CurrentValueChanged +=
        this.Gyroscope_CurrentValueChanged;
      this.m_gyroscope.Start();
    }
    catch (Exception) { this.m_gyroscope = null; }
  }
}

The Gyroscope_CurrentValueChanged method just writes a line with obtained data to the output, thus you can analyze them in the Output window. It is worth mentioning that you can access angular velocity along x, y, and z axis by the RotationRate property (of the GyroscopeReading instance) and its X, Y, and Z properties, as shown in the following code snippet:

private void Gyroscope_CurrentValueChanged(object sender,
  SensorReadingEventArgs<GyroscopeReading> e)
{
  Debug.WriteLine("Gyroscope data: {0} (x in rad/s), {1}
    (y in rad/s), {2} (z in rad/s)",
    e.SensorReading.RotationRate.X,
    e.SensorReading.RotationRate.Y,
    e.SensorReading.RotationRate.Z);
}

To write values to the output, the WriteLine static method from the Debug class is used. This class is located in the System.Diagnostics namespace.

Similar to the accelerometer usage, you should ensure that the gyroscope is stopped as soon as it is no longer used by your application:

public void OnNavigatedFrom(NavigationEventArgs e)
{ (...)
  if (this.m_gyroscope != null)
  {
    this.m_gyroscope.Stop();
    this.m_gyroscope = null;
  }
}

After launching the game on the phone equipped with the gyroscope sensor and connected to the PC, you should see data obtained from this sensor in the Output window.