Imagine humming the notes of a song. What if a small app could recognize the notes and play them back in real time using a sound recorded from a musical instrument.
You could play the piano or saxophone by humming softly into your iPhone and letting the app do the conversion work for you.
This will bring the playing ability to people that did not spend years practicing a specific instrument but have the capacity to sing or hum the right notes.
This is a creative idea but I found out that there are several patents that are very close to it so it is off the implementation list..