PitchDetector is a precise software implementation of chromatic tuner. Pitch of recorded sound can be measured up to 10 times a second.Free version: sometimes a popup-window with a link to the popup-free version appears.System requirement:sound recording with a sample rate of 44100 Hz.Features:reference frequency (a') can be adjusted in the range of 400 to 500 Hz,you can select one of four musical notation systems,you can adjust brightness of display (eg. to save battery life)