iOS app · Available on the App Store

Deconstruct chords
by ear.

jAMSKOOL · Build

A root plays. Tones move against it. Find them. Five rounds, three difficulty levels, two modes. Compete against the world or against yourself. Pure ear, no theory required.

Download on the App StoreAvailable on iPhone · $2.99 USD
jAMSKOOL Build — Home screen

How it plays

Pure ear. No theory.

A root note plays. Two or three tones bend in around it. The timer keeps track of your struggle.

Find the tones
A root settles in the centre. Tones bend in around it. Tap the scale degrees you think are playing, then submit when you've got it.
Race the clock
Five rounds per run. Total time across all five is your score. Sub-second precision — every fraction counts.
Two modes, your call
Hard mode: one wrong tap ends the round, and a perfect run posts to the world leaderboard. Soft mode: a 10-second penalty instead, just for you.
Three difficulty levels
Diff 1 sticks to friendly intervals. Diff 2 widens the colour palette. Diff 3 is anything goes. Build up.
Two- or three-tone chords
Toggle between two-tone stacks (cleaner, faster) and three-tone voicings (thicker, harder to untangle). Same game, different depth.
Play the world
Land a perfect run in hard mode and post your time to the global leaderboard. Top 100 per tone-count and difficulty.

A look inside

Five rounds of pure ear.

From setup to perfect run — what every session looks like.

Round 1, two tones with wave tendrils to root

A root plays. Tones move against it. Find them.

Round with three tones, violet and teal voices

Three-tone mode adds depth — and a third colour to track.

Correct answer, both tones glow violet under the root

Tones light up violet when you nail them.

Wrong answer in soft mode showing the actual chord tones

Wrong tap in soft mode — the chord is revealed, the timer keeps going.

Perfect run summary with five round times

Five rounds, total time, new personal best — and a share card.

Round failed screen in hard mode after one wrong tap

One wrong tap in hard mode and the round's over. Try again.

Pricing

Pay once. Keep forever.

No subscription. No in-app purchases. No ads. No account. Just the app.

One-time purchase

$2.99

USD · one-time

Download on the App Store →

jAMSKOOL Build collects only what's needed to run the world leaderboard: a randomly generated user ID, a chosen display name, and your round times. No account, no email, no tracking, no ads. The leaderboard is fully optional — if you stick to soft mode, nothing leaves your device. Full privacy policy →