Proximity sensor Ambient light (ALS) Global positioning system (GPS) Accelerometer Compass Gyroscope
Very useful in touch based Mobile Phones. While on call and you bring the device near your ear, Proximity Sensor detects it and can turn off the screen to avoid accidental touch of the screen by ear.
An ambient light sensor to portable devices such as tablets, smart phones, and laptops extends battery life and enables easy-to-view displays that are optimized to the environment.
The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was originally intended for military applications.
The accelerometer in mobiles (like the iPhone) is used to measure the orientation or vertical and horizontal positioning of the phone. The most basic application of this is the device knowing when to alternate the view of the screen depending on how you are holding it.
The digital compass thats usually based on a sensor called magnetometer provides mobile phones with a simple orientation in relation to the Earths magnetic field. As a result, your phone always knows which way is North so it can auto rotate your digital maps depending on your physical orientation.
A gyroscope is a device for measuring or maintaining orientation, based on the principles of angular momentum.