If anyone know about an accelerometer app that would play some sound when a certain threshold is reached. or play a beep that increases in freqency, from one threshold to another, like, one beep a second, up to 4 beeps a second, when reaching some acceleration level, quiet below the threshold level. The obejective would be to train for a better car driving habit. All apps on the market have visual indicators for acceleration, but none have an audio monitor. Note: The phone is not necessarly flat in the car, so, some calibration would be required, when stopped, then when driving forward to detect the FORWARD vectorial displacement, being a combinaison of all 3 axis. That should not be too hard to do?