Why three (redundant?) Variations of the accelerometer in Android sensors

Question

In android, we have Sensor.TYPE_GRAVITY, Sensor.TYPE_ACCELEROMETER, Sensor.TYPE_LINEAR_ACCERERATION.

And from the Android Developers Forum, we know that, "The output of the accelerometer, gravity and linear acceleration sensors should correspond to the following ratio: acceleration = gravity + linear acceleration"

Sensor.TYPE_GRAVITY and Sensor.TYPE_LINEAR_ACCELERATION use the same sensor as Sensor.TYPE_ACCELEROMETER - that is, an accelerometer? What is the purpose of having 3 different constants if the value of one can be derived using the other using low-pass and high-pass filters?

Answer 1

, TYPE_LINEAR_ACCELERATION TYPE_GRAVITY API 9 (Android 2.3). API, TYPE_ACCELEROMETER ( API 3). TYPE_LINEAR_ACCERERATION TYPE_GRAVITY TYPE_ACCELEROMETER. Android 2.2 ( API 8) , !

: http://developer.android.com/reference/android/hardware/Sensor.html

Answer 2

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