RTTATuner

RTTA, short for Real Time Tuning Analysis, is an innovative way to tune instruments and to analyze and improve your intonation. With a conventional instrument tuner, you play a single note, and the tuner indicates how well in tune that one note is. For variable pitch instruments like the flute, this can be deceiving. What is needed is a way to analyse the intonation of all notes in a piece of music or scale, as performed naturally. This is exactly what the RTTA technique provides.
Now, for the first time, the RTTA technique is available to iPhone users in the form of RTTATuner. Press the record button, and play a piece of music or some scales. RTTATuner will display the tuning of each note on a graph that is updated in real time. Choose from popular musical temperaments, or input custom temperaments. Select the pitch standard, temperament transition, display options, and note filters. Analyse your performance intonation or test the intonation of particular fixed and variable pitch instruments. Results can be exported to PDF for later reference.
RTTATuner will prove useful to all kinds of musicians and instrument makers. I hope you enjoy using it; please consider providing feedback on the app store!
Credits and Thanks:
The RTTA concept was invented by flutemaker and researcher Terry McGee, and was first put into practice by Graeme Roxburgh. See also Scott Turner's Windows application, Flutini, and the Tartini software developed by Philip McLeod and others at Otago University. Thanks go to all of the above.
The RTTATuner app was designed and developed by Dan Gordon.