Beatwheel

The strobe tuner that holds a drone while it listens.

The disc stands still when you are in tune, and a drone keeps sounding while Beatwheel measures.

Get it on Google Play

USD 3.99 once. No ads, works offline.

Tune screen for a Baroque oboe profile at A 415.0 in Werckmeister III, the strobe disc still on A4 at 0.0 cents

Stillness is the signal.

A 4

Sharp turns it clockwise.

Flat turns it back.

In tune it stops.

Tune screen with a reed drone on A3 playing and the readout showing 0.6 beats per second, sharp, at 415.6 Hz

A drone that keeps sounding while you tune

Start a sine, reed or saw drone on any note from octave 2 to 5. It follows the same reference and temperament as the meter, so you can play into it until the beats stop.

With headphones the drone never reaches the microphone. On the speaker, Beatwheel removes its own drone from what it hears, and near unison the readout switches to the beats per second you can hear.

See how far a held note drifts

Record a held note for up to an hour, ten readings a second. Name the session, then export it as CSV or share it with the section.

Start, cents
+1.7
End, cents
-10.0
Cents a minute
-0.29
Session detail for Tuesday brass: a 42 minute chart of cents against minutes sagging from +1.7 to -10.0 with a break near 21 minutes, with start, end, range and cents a minute

Export CSV

session,started_at,elapsed_s,written_note,sounding_note,target_hz,measured_hz,cents,reference_a_hz,temperament,profile,gap
Tuesday brass,2026-09-08T18:02:00+05:30,0.0,C5,Bb4,466.16,466.66,1.8,440.0,Equal,Trumpet in B flat,0
Tuesday brass,2026-09-08T18:02:00+05:30,1260.0,,,,,,440.0,Equal,Trumpet in B flat,1
Tuesday brass,2026-09-08T18:02:00+05:30,2519.9,C5,Bb4,466.16,463.61,-9.5,440.0,Equal,Trumpet in B flat,0

One row per reading, with the written and sounding note, target and measured hertz, and cents, plus a gap row wherever the app was in the background.

Set up for the instrument in your hands

Edit profile screen for Baroque oboe with A4 at 415.0 Hz and Werckmeister III selected
A from 415 to 466 in 0.1 Hz steps, and six temperaments on any tonic.
Clarinet in B flat in dark mode, reading a written D4 at +1.2 cents with the sounding C4 beside it
Transposing instruments show the written note large and the sounding note beside it.
Stand mode in dark mode on the Harmonium profile: the strobe disc fills the width above a large C sharp 4 at -0.5 cents, 277.1 Hz
Stand mode fills the screen and keeps it on through a rehearsal.

Temperaments

Equal, just, Pythagorean, quarter-comma meantone, Werckmeister III and Kirnberger III, plus your own twelve cents offsets.

Fifteen instrument profiles

Chromatic, guitar, ukulele, violin, viola, cello, double bass, flute, oboe, clarinet, alto and tenor saxophone, trumpet, horn and harmonium. Copy any of them to make your own.

Calm between notes

A noise gate and a sensitivity setting with a live input meter, and a held-tone mode for oboe and harmonium that averages over a longer window.

Your data stays on the device

Profiles, temperaments and sessions go out as one backup file and come back in. No audio is ever saved. If you decline the microphone, the drone, profiles and sessions still work.

USD 3.99Paid once on Google Play. INR 149 in India.

One-time purchase. No ads, no subscription, no account. Works fully offline.

Beatwheel asks for the microphone and nothing else, and has no internet permission. It does not include a metronome, harmonic-by-harmonic strobes, or drum and tabla tuning.