Kritus

Real musical ability lives in your ears — not on a page.

Kritus is not music theory, and it is not lessons. It doesn't ask you to read, memorize, or recite. It trains the one thing every musician actually runs on — the ear. You hear a note, a chord, or a phrase, then find it on your instrument by sound alone.

NO BACKGROUND NEEDED — AND NO WAY AROUND IT
You don't need to read music. You don't need theory, or years behind you. But if you want to truly hear — to play what you imagine, pick out the music you love, and find your way through any song — there is only one path, and your ears have to walk it. Kritus is that path, from your very first note.

PUT THE PAGE AWAY
No sheet music. No fretboard diagrams. No keyboard maps. Kritus never shows you where to put your fingers, because reading the answer is not the same as hearing it. You listen, you search for it on your instrument, and you play it back — the microphone checks what you played, entirely on your device.

WHAT YOU'LL PRACTICE
- Single notes, intervals, chords, phrases, and full chord progressions.
- Chords that open up: when one is hard to hear, its voices gradually separate so you can catch each on its own, then settle back into a single sound.
- The River, which carries you through everything in the order real music actually uses it — practice and review woven together, always moving.
- Guitar or piano, with reference sounds recorded from real instruments. A built-in guitar tuner, too.

PRIVATE BY DESIGN
Microphone audio is analyzed on your device in real time and immediately discarded — never recorded, saved, or uploaded. No accounts, no ads, no analytics.

SUBSCRIPTION
Kritus Serious User unlocks the whole app after a 7-day free trial:
- Monthly — $8.99 / month
- Annual — $49.99 / year
Payment is charged to your Apple ID at confirmation and shown in your local currency. The subscription renews automatically at the price shown unless cancelled at least 24 hours before the current period ends. Manage or cancel anytime in your App Store account settings.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://kritus.marcuslabs.ai/privacy