Use ancilla in a sentence. an aid for use as in understanding or accomplishing something; often, specif., a handbook, or manual. Origin of ancilla. see ancillary.
Making the world better, one answer at a time. The accelerometer in mobiles 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 use of the accelerometer in the iPhone is similar to that in the Wii, although on a smaller scale. The movement and tilt of the device is noted by the sensors, so it can tell which way the screen is being held.