Chordrill - Full app for iPhone and iPad

This app is for training on chord analysis (harmonic analysis), which is very important for analyzing music. It will give a variety of questions with different keys and difficulties so that you can improve your skills on chord analysis efficiently.

This apps preview: https://www.youtube.com/watch?v=6IP70_0bbHw

=== Main Feature List ===
* Selecting a level of difficulty from Intro I, Intro II, Easy, Moderate, and Difficult.
* Questions with a variety of chords (diatonic chords and alternative chords).
* Support of inverted chords.
* Playing and arpeggiating a chord.
* Report section to show your performance report.

* Selecting a key from fifteen major and fifteen minor keys.
* Selecting a clef.
* Keeping a list of questions with flags so that they can be reviewed later.