Chord -

It uses a "circle of fifths" visualizer to show which chords fit a specific key.

Reviewers from Audio Science Review note it offers a "clean run" for almost any headphone and is highly competitive for its size. Mindful Harmony (Chord Progression App) It uses a "circle of fifths" visualizer to

“It's a DAC/amp you can drop in your pocket and get a clean run from all but the most power-demanding headphones.” It uses a "circle of fifths" visualizer to