Spectrolite app for iPhone and iPad

Spectrolite visualizes the frequency content of sound in real time in the form of a spectrogram.

Spectrolite uses a constant-Q transform, a kind of wavelet transform, to scale the frequency resolution with the frequency being analyzed. This results in a perceptually and musically meaningful spectrogram where different frequencies appear as equally sharp traces on a logarithmic frequency scale, and where the notes on a musical scale are evenly spaced.

The display covers the full frequency range of human hearing. Intuitive touch panning and zooming lets you dive in and explore the spectrogram in detail.

The Pro in-app purchase adds grids and scales for time, frequency, and amplitude, as well as a spectrum view and a tap-to-measure function. This expands Spectrolite into an audio measurement tool that you can use to measure frequencies, musical pitches, amplitudes, and durations.