Twelve open-position guitar chords, strummed perfectly in tune. Tap one, then play the same chord on your guitar — if yours sounds sour against it, you know which job comes first.
Tap a chord to hear it.
The after-tuning check. A tuner proves each string individually; a chord proves them together. Tune with the tuner, strum an E here, strum an E on your guitar. If they don't agree, something slipped — usually the string you tuned first (our guitar guide explains why the second pass matters).
Ear-tuning trainer. Arpeggio mode plays the chord one string at a time, slowly. Match each of your strings to it by ear, then grade yourself with the tuner. It's the same beat-listening skill from our ear vs tuner guide, with a friendlier reference than a bare sine wave.