Chord Doctor is an app designed to help you master the basic materials of music. It conveniently divides the facts of music into units that can be mastered in a reasonable amount of time. And there is a teacher’s logic built into the app. If you answer a question incorrectly, that question returns with increased frequency until you can answer it with confidence.
There are many reasons for learning music theory. Some students need to learn it because it is a required part of their private music lessons or because they must demonstrate a proficiency in theory to compete in music festivals. Others want to learn theory in order to lay a foundation for keyboard improvisation. For some, music theory is a requirement in a college music curriculum, for others, it is a subject that simply helps them understand the inner workings of the astonishingly beautiful art of music.