platform provides two sensors that let you determine the position of a device: the
geomagnetic field sensor and the orientation sensor. The Android platform also
provides a sensor that lets you determine how close the face of a device is to an object (known as
the proximity sensor). The geomagnetic field sensor and the proximity sensor are hardware-based.
Most
handset and tablet manufacturers include a geomagnetic field sensor. Likewise, handset manufacturers
usually include a proximity sensor to determine 