ALL LEVELS/MODES ARE NOW FREE (donations still appreciated).Clef Mastery: Teaches you the notes of the treble and bass staff level by level.Lightning Mode: Switches between treble and bass clef, and keys.Instrument Mode: Lets you become familiar with your actual instrument. Includes a mode for when you dont have your instrument with you, and a m…... 展开 更新内容： 为您优化了体验细节。