SoundMeter for iOS turns your device into a handheld data-logging sound level meter.
Input signals can be acquired from the current audio input path (iOS automatically selects the audio input path according to which external audio devices, if any, are connected to your iOS device). Sensitivity calibration can also be performed for any audio input device or input channel. (See Calibration)
In addition to real-time sound level measurements, SoundMeter can stream raw sound data to audio files, and store acquired sound level data, including date, time, and location, in CSV or TXT (tab-delimited) files, MAT-files, or high-resolution PDF images for later retrieval from your device. (See Data Acquisition)