Sound Meter description

Professional sound level meter that measures loudness or sound pressure (SPL) in decibels.
If features direct reading in dB or dBA, wide measuring range, Min/Max function and additional digital display.

NOTE: This app can measure sound level in decibels using your device's microphone located on the bottom. The accuracy of the measured sound level depends on your device's microphone quality and can be improved by calibration procedure described in app's info screen.