ne note at a time

A quiet workbench for pitch, time and harmony.

A strobe tuner, a living scope, a three-layer metronome, a harmony page that answers questions, and a recorder that is also a looper and writes down what you played. It shows you what your sound is doing and stays out of the way.

Get it on TestFlight Open it in the browser

In public beta for iPhone. Pay once when it ships — no account, no cloud, no analytics. Nothing leaves your phone.

The desk: scope, tuner, metronome and recorder in a column over a keyboard, with a chord held — The desk. One held chord, read four ways.

6scope views

35chord formulas

7loop layers

8guitar tunings

6tuning systems

0accounts or servers

Overview

Five things it does, on one desk.

The desk is the home screen: four widgets in a column over a keyboard that sounds while you touch it. Each widget's title opens its own deeper page. Here they are, one at a time — it turns on its own, and stops the moment you touch it.

Tuner

Strobe, needle, and the note in its key.

Three strobe bands drift at the rate you are off, so a slow crawl is a few cents and a standstill is in tune. Hold a note true for half a second and the display glows, once, softly. Tap Key, sing the root, and the whole app is in your key.

Readout: Detected and target frequency, clarity, level, cents to a tenth.
In the key: The note's degree and its interval from the tonic, on a strip of all twelve.
Chords: Hold two or more reference keys and it names the chord.
Strum: A whole tuning at once for guitar and bass: every string, every deviation.
Reference: Two octaves of keys on the page that light the note you sing, so a pitch to sing against is one touch away.
Concert pitch: A4 from 380 to 500 Hz, and six tuning systems: equal, just, Pythagorean, meantone, Werckmeister III, Kirnberger III.

The tuner: strobe bands, needle and the note placed in its key

Scope

Six views of the same air.

Frequency over time, drawn in the key's colours so chords appear as bands. Tap anywhere for the exact frequency, note and interval. Freeze it, clear it, or slow the timebase down and read overtones like terrain.

Musical: Melody against the key. Colour carries pitch class; the tonic lane is tinted.
Design: A spectrogram with contrast and relief shading for sound design.
Spectrum: A third-octave analyser on a fixed dB scale, with peak hold and freeze.
Wave · Stereo: The waveform, triggered so it stands still; a goniometer with a correlation meter.
Cymatics: A plate that settles into nodal lines for the note you hold.
Shelf: Listening reads the key and chord in the room. Acoustics turns a frequency into a wavelength and a delay time. Signal sends a sine, pink noise or a sweep at a level in dBFS.

Scope, musical view: a chord as coloured bands over time

Scope, cymatics view: a plate settling into nodal lines

Theory

Harmony as a question, not a lesson.

Set one key — by playing it — and the page answers: which chords live here, which can be borrowed, where the secondary dominants sit. Chord colour encodes function, so the tension of a progression reads at a glance.

Chords: Thirty-five formulas from triads to thirteenths, inversions, extensions, borrowed chords as ghosts in their own column.
Slide: Hold a chip and slide: up for 7 · 9 · 11 · 13, down for sus4, sus2 and the bare fifth, sideways to turn it over. A card maps the whole reach; tap a cell with the other thumb.
Voice-led: Chords step to their nearest notes and stay on the keys you can see, so a walk up the scale never runs away. Or free, with the root pinned in the bass; or spread, the hand opened out.
Arp: Up, down, random at a rate, or a bar of hits by genre — Alberti, bossa, shuffle, tresillo — with a little human drift; a chord that changes mid-air glides to the next.
Rings: A chord under two thumbs: a family on the left, a root on the right; slide to climb or turn it over.
Scales: Twenty-four scales with degrees, diatonic harmony and roman numerals — and your own, played in.
Circle · Frets: A circle of fifths that sets the key and draws your progression; a fretboard in eight tunings lit with the chord you chose.
Progression: Record one as you play — to the click, each chord as long as you held it — sixteen bars a section, A into B into C; reshape, transpose, keep. Twenty-eight worked examples.
Written pitch: Names and keyboards move to a B♭, E♭ or F instrument, or a capo, while the tuner stays in concert pitch.

Theory: the key's chords, borrowed chords and secondary dominants over a keyboard

Metronome

Three layers, real time signatures.

Pulse, accent and subdivision are separate layers you can mute or shape. 6/8 pulses like 6/8; 7/8 groups two, two and three. Tap a beat to accent or silence it. The pulse taps back through the phone, so you can keep time with it in a pocket.

Tempo: 30 to 300 BPM, 1 to 1111 if you ask for silly; tap it in, or drag the number.
Signatures: Simple and compound, with grouping. Beat one is always a quarter-note pulse.
Subdivision: Eighths, triplets, sixteenths, up to eleven in a beat; swing on any of them; ms·Hz turns the tempo into note values in milliseconds and hertz for delays and LFOs.
Groove: A kit or the theka of a tala under the click, tuned to your key.
Seq: Bars of one meter, then another; the tempo kept, related or ramped — a tempo trainer.
Poly: A second pulse against the first — three against two, or any pair — with its own sound and level.
With the looper: Loops of one, two, four or eight bars count in on its click and keep it as a lane.

Recorder · Looper

Record, loop, keep — under one pedal.

One button at the foot of the page is the pedal: tap to record, tap to close the loop, tap to overdub, tap to play. Up to seven layers, then resample and go again. Layers of other lengths run against each other. Hold the pedal to undo. And every take is a voice note that knows what you played: each chord and key change written down against the audio clock.

Loop: Free — the loop closes on your note — or one, two, four, eight bars on the click. Half and double speed, turned over, resampled.
Snap: A layer's attacks moved onto a grid of 8, 16 or 32 steps a pass. Slices move, never stretch. Undo is a hold away.
Source: The room, the keys, or both — with the keys delayed into the take so they land where you heard them.
Marks · tags: Drop a mark while it runs; #idea #keeper #fix #tuning, or your own.
Meters: Peak, held a moment; RMS; loudness in LUFS — readable, four times a second.
After: Lanes with gain, tone, pan, level and space; the notes it heard, several at once, drawn on a roll and read as chords bar by bar, out as MIDI or a .mid file; Words turns a voice note into text, on the phone. Share a take as WAV. The library stays on the phone.

Records: a loop running under the pedal, with the keys up

Records: a take opened — the wave over the click lane, the layer's knobs, and Read for the notes it heard

Out of the phone

A controller for your studio, a widget for your thumb.

Plug the phone into a Mac and every key, chord and arpeggio leaves as MIDI — Ableton, Logic or anything else sees an input called iPhone. Six doors on the home screen jump straight to a page, in the app's colours or your own. And the sound itself: every voice filtered by pitch and touch, a soft saturator in front of a gentle limiter, a dark tail. Easy on the ear, by design.

MIDI out: Over the cable, stamped on the beat. Theory chords trigger instruments on the computer.
Widget: Desk · Scope · Tuner · Metronome · Records · Theory, small or medium, eight skins.
Voices: Piano, E-Piano, Strings, Organ, Pluck, Sine — a pure tone, so beats between mistuned intervals are plainly audible.
Setup: Concert pitch, tuning system, how notes are named, the instrument you write for, bend and glide, where the sound plays. Change one, and every page follows.
Look: Ink, in the dark or with the lights on. The displays stay dark either way.

MIDI out

Plug it in. Play the chords. Hear your studio.

Over the cable, the phone is a MIDI controller. Every key you touch, every chord chip, every arpeggio leaves as notes, stamped on the beat, and your DAW sees an input called iPhone. Ableton, Logic, anything that takes MIDI. The Theory page becomes the quickest way to try a progression on a real instrument.

Cable. The phone into the Mac, USB.
Once. In Audio MIDI Setup, enable the phone under Inter-Device Audio & MIDI.
Play. Pick iPhone as the input of a track. Tap a chord.

Apps on the phone itself see the same port, named One Note. MIDI in and clock are next.

What people reach for it for

One app, quietly a dozen tools.

It is trying to do a lot at once, on purpose: the things you otherwise open five apps for, in one that shares a key. Some of them.

Tune a guitar in a loud roomStrum once; six strings, six readings.
Find the key of a song by singing itTap Key, hum the root. Everything else follows.
Loop a vamp and sing over itTap, play, tap. Overdub seven times. Keep the one you like.
Hear what a vi chord doesTap it in your key and watch the tension colour change.
Set a delay time from the tempoNote values in milliseconds, right under the BPM.
Check a mix is mono-safeA goniometer and a correlation meter, in your pocket.
See a vowelSing into the cymatics plate and watch it settle into lines.
Keep a 2 a.m. idea with its chordsThe take remembers what you played and when.
Practise 7/8 until it feels like 4/4Two, two, three — and the phone taps your palm.
Send chords to Ableton over the cableThe Theory page as a MIDI controller.
Check your intonation on a held noteA strobe readable to a tenth of a cent, and a bloom when you are there.
Be tuning one second after you thought of itA widget on the home screen opens the page you want.

Price

€11. Once.

Less than a clip-on tuner, for a tuner, a scope, a metronome, a looper and a harmony page that answers back. One payment, everything in it, every update after. No subscription, no unlockables, no account to make, no ads to look at. Family Sharing on.

€11

pay once · iPhone · iOS 17 or later

TestFlight beta · invites by hand for now

The beta is free while it lasts. The App Store listing follows; the price above is the price it will be.

The same workbench runs in a browser at /app, for the desk beside the DAW. The phone has the mic and the keys through its own audio path.

Look

One skin, two moods.

Flat, warm and typographic. Warm near-black in the dark, warm paper with the lights on. A display is always a screen, whatever the room is doing.

Ink, in the dark

Ink, with the lights on

Private by construction

Your sound is nobody's business.

No account. No cloud. No analytics. Your recordings, your progressions and your practice stay on your phone, not as a policy but as an architecture. There is no server for them to reach.

The microphone is asked for once, in the app, and used only for live analysis and for takes you choose to record. The picture never leaves the device, and neither does the sound — unless you keep takes in iCloud, a switch in Setup that is off until you turn it on, and then only to your own iCloud. The one other thing that ever leaves is a note you write in Feedback — with a picture of the page, if you attach one — and only when you tap Send.

Pay once and it is yours. Read the privacy policy.