1. DESPLAY
The spectrogram of voice is displayed in the range of 20 - 2500Hz.
You can zoom in/out the spectrogram by pinching in/out smoothly.
Also landscape orientation is supported.

2. USEFUL
By moving "vivid" slider, the gradation of spectrogram is controlled.
The gradation is also controlled by moving "baseline" slider in "Setting" tab and selecting "Mean" or "RMS" as the way of smoothing the spectrogram out.

3. LOGGING
When "log" switch is ON, this app runs in the logging mode.
To choose a past log from "History" tab, you can pull it from iPhone via email as a PNG file.

4. AVAILABLE
Without cellular data service, the full functions are available.
The background processing is supported.

5. TECHNICAL NOTE
Sample rate: 44.1kHz
Bit depth: 32bit float
FFT window function: Blackman
FFT samples: 4096