Tuner — Chromatic Tuner

Tuner is a chromatic tuner. It opens listening: no instrument to pick, no
string to select, no tutorial.

Play a note and it tells you which one, and how flat or sharp. The needle moves
with the string, with no easing that would make it look settled while the
string is not.

• Note, octave and frequency: A4 · 440.0 Hz
• Cents, with a direction: left and blue when flat, right and rose when sharp —
the colour and the side say the same thing twice
• Inside five cents the needle enters the gate and the measurement becomes the
word "In tune": that is the answer you opened the app for
• Two beats when the string is right, one short tick when a new string is
heard: you tune with your eyes on the peg, not on the phone
• The strings drawn on the background vibrate with what the microphone hears:
the only honest sign that the app is really listening

Reference pitch and tunings, for whoever needs them:
• reference from 415 to 466 Hz — baroque, 432, or an orchestra at 442
• guitar: standard, drop D, half step down, open D, open G, open E, DADGAD
• 4- and 5-string bass, ukulele, violin, viola, cello, mandolin, banjo, Irish
bouzouki (GDAD and ADAD)
• with a tuning chosen, the cents are measured against the string you are
aiming at rather than the nearest semitone: on a badly flat string those are
two different answers

It stays chromatic at 440 Hz until you touch anything.

What Tuner does not do:
• no account, no sign-up
• it does not record: the sound is analysed in the phone's memory and
thrown away, and no file is ever written
• no location, no servers of ours

Note detection uses the YIN algorithm, the one that stops a guitar's low E from
being reported as the E an octave below. The maths is checked by automated
tests against synthesised tones before every release.

Permissions: microphone (to hear the string), Internet (ads only) and
vibration. The app is free and paid for by ads: a banner at the bottom, away
from the controls, and an occasional full-screen ad only after the string is
where you wanted it.

Privacy policy:
https://mindcontact.app/mcma-tuner/privacy/