FFTWave is an iPhone app developed by Eisaku Nozu that serves as a handy tool for viewing and analyzing sound waveforms. The app allows users to visualize sound waveforms captured from the microphone, providing a clear representation of audio data. Additionally, FFTWave offers a spectrum display through Fourier transform, enabling users to examine the frequency characteristics of the sound they are analyzing.

Moreover, FFTWave comes equipped with useful features such as peak detection and peak hold, enhancing its functionality for sound analysis purposes. Users can also take advantage of Pinch Zoom Gestures for a more detailed view of the waveform, aiding in sound adjustment and howling analysis.