li>
    <li><a href="#sensors-pos-mag">Using the Geomagnetic Field Sensor</a></li>
    <li><a href="#sensors-pos-prox">Using the Proximity Sensor</a></li>
  </ol>
  <h2>Key classes and interfaces</h2>
  <ol>
    <li><code><a href="../../../reference/android/hardware/Sensor.html">Sensor</a></code></li>
    <li><code><a href="../../../reference/android/hardware/SensorEvent.html">SensorEvent</a></code></li>
    <li><code><a href="../../../reference/android/hardware/SensorManager.html">SensorManager</a></code><