An accelerometer is
|“||[a] device that measures acceleration (the rate of change of velocity). An accelerometer inherently measures its own motion (locomotion), as opposed to a device based on remote sensing.||”|
|“||measures the acceleration an object experiences relative to free fall. Accelerometers can, for instance, be used to measure vehicle acceleration. In most smartphones, the accelerometer is used to present landscape or portrait views of the device's screen, based on the way the device is being held.||”|
Single- and multi-axis models are available to detect magnitude and direction of the acceleration as a vector quantity, and can be used to sense orientation, vibration and shock. Miniaturized accelerometers are increasingly used in portable electronic devices and videogame controllers, to detect the orientation of the device or provide for game input.