Intonia

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.
The free version is limited to one minute of sound storage, A=440, equal temperament.
An in-app purchase will upgrade to the Pro version. The Pro version includes the following:
* 'A' frequency settable between 400 and 499 Hz
* Choice of Equal, Pythagorean, or Just intonation.
* Save and restore audio files
* Rename or delete audio files
* Import and export audio files from/to iCloud
* Up to 60 minutes of sound storage
* Screen is kept on during recording and playback
* Playback and record in background mode while the screen is not showing
Here are some things you can do with Intonia:
* Play a fast passage, and see which notes were out of tune.
* See intonation in just, Pythagorean, or equal temperament.
* Tune your instrument.
* Use as a digital recorder to hear yourself play.
* Get instant feedback.
* Visualize articulations, slides, shifts, vibrato, etc.
* Use it for transcription.
* Works for all string instruments: cello through violin.
* Works for many other instruments as well.
For more information, please visit our website at http://intonia.com/