1) It takes sound signal from the Microphone.
2) It measure and compares the sound signal level with the threshold which you set.
(You could set the Audio Sensor Threshold in dB's)
3) If sound signal level greater than the threshold which you set, the App will makes you phone vibrating.
(You could set the vibration time in milliseconds)
* External microphone, for example on headphones, is more preferable than microphone builtin in your device, otherwise the close loop possible and selfresonance could happen
** Different devices has different sensor manufacturers, so they could have different sensitivity from device to device. Also, with the time the sensitivity of sensor could change for one device, also temperature, humidity and atmospheric pressure could influence on the microphone sensitivity. For this we include in the app the Audio Sensor Sensitivity Adjustment via the Audio Sensor Threshold seekbar widget.
*** Different devices has different parameters of eccentric vibration modules, so adjust/set the vibration time exactly for your own device and your own preferences to feel the vibration feedback