Intonia is a Pitch Recorder. It's software intended to help string players visualize intonation. It combines the capabilities of an electronic tuner and a digital recorder. It keeps a memory of what it has heard, and displays pitch on a scrolling graph. You can specify what temperament to use: Equal, Just, or Pythagorean.

While it is recording, the display scrolls continuously. Your pitch is displayed as the height of the trace. If you're playing in tune the trace is white, but if you're sharp relative to your chosen scale and temperament, the trace is colored red. If you're flat, the trace is blue.