NoiseExplorer

NoiseExplorer is a sound level meter app. It computes sound pressure level and frequency spectrum from the audio received from the default microphone of the phone. The app records the current location of the device as well as the calculated sound pressure level to a log file every five seconds. These log files can be accessed using File Sharing in iTunes and used for generating noise maps. Optionally, the app can also record WAV files which can be used for further analysis on a PC. Note that the app needs a calibration file to compute sound pressure level accurately.