I want to create an app that would be able to use the phone's microphone in order to get the outside noise volume in db. What is the easiest way to do it?
Check out one of the two projects on code.google.com:
http://code.google.com/p/moonblink/wiki/Audalyzer
http://code.google.com/p/splmeter/
where as the last projects used this formular for calculating the sound pressure value: