A PeaceDrone Product

The tuner for every instrument in your collection.

Coming to the App Store

Three Distinct Meter Modes

SuperTuner on iPhone, LED arc + chromatic strip, Bass standard tuning, A1

LED ArcBass Standard

SuperTuner on iPhone, Chromatic wheel + fine-tune cents ruler, Guitar standard, E

Chromatic WheelGuitar Standard

SuperTuner on iPhone, Stroboscopic meter + info bar 98.1 Hz G2, Cello tuning

StroboscopicCello

Each main meter is paired with a sub-meter underneath. Tap to cycle independently, or hit the Mode button to flip both at once through three matched setups.

Snappy,
like a pedal tuner

LEDs arc across the display, centering when you're in tune. Below them, a chromatic strip shows your note relative to the target. It's simple, reliable, and easy to use.

iPhone, LED arc meter with chromatic strip, Bass standard tuning, A1

The note in the context of the musical spectrum

The chromatic wheel shows where you are, and a fine-tune cents ruler sits underneath. It's the logical flip of the previous mode, with the big picture up top and the fine tune below.

iPhone, Chromatic note wheel with fine-tune cents ruler, Guitar standard tuning, E

Real phase velocity, like a hardware strobe

Four rows of bars represent the fundamental and three harmonics. When they drift left you're flat, when they drift right you're sharp, and when you freeze them in place you're perfectly in tune. You'll increasingly notice the difference between close enough and in tune.

iPhone, Stroboscopic meter with info bar showing 98.1 Hz G2 +2.3 cents, Cello tuning

Cycle the pairings,
or mix them

Tap either face directly to cycle just that one. The Mode button advances both together. Any main meter pairs with any sub-meter.

#
Main Meter
Sub-Meter
1
LED Arc
Chromatic Strip
2
Chromatic Wheel
Fine-Tune Cents Ruler
3
Stroboscopic
Info Bar

Tune by ear,
like in the long ago

Before modern tuners, everybody tuned by ear. In the classical days, tuning forks were carefully transported between countries to establish common reference standards. A few hundred years on, folk musicians tuned to a pitch pipe. It works, and it builds the ear, deepening the connection between musician and instrument.

So we included a tone generator for every preset. Since tapping buttons on and off is no fun, we put it on an adaptive ribbon controller. Swipe your finger to audition a new tuning, or tap a note name to hold a reference. Latch up to three notes at once to hear interval relationships. It's a great way to explore the presets.

Designed to help you explore new tunings

Guitar features 17 tuning presets, or 22 if you count baritone and 7-string variants. Beyond guitar, SuperTuner supports 15 other instrument families: bass, orchestral strings, ukulele, banjo, mandolin, sitar, charango, bouzouki, you name it. Ever thought about tuning your guitar to the notes of a sitar? Now you can.

Group
Count
Examples
Open / Chromatic
1
Chromatic: no preset constraint, detects every note
Guitar
17
Standard EADGBE, Drop D, Drop C, Open D/G/E/A, DADGAD, Math Rock, Nashville
Extended Guitar
5
Baritone B & A, Drop A, 7-string, 8-string
Bass Guitar
6
Standard EADG, E♭, D Standard, Drop D, 5-string, 6-string
Orchestral String
5
Violin GDAE, Viola, Cello, Double Bass standard + solo
Mediterranean Folk
6
Mandolin, Mandola, Octave Mandolin, Irish + Greek Bouzouki, Bandurria
Ukulele
4
Soprano, Tenor (low G), Baritone, U-Bass
Banjo
11
Open G, Sawmill, C, Double C/D, Open D, G minor, A; Plectrum, Tenor variants
Steel Guitar
7
Lap C6/E7/Open E/Open D, Dobro, Pedal E9, Pedal C6
Latin Folk
12
Charango, Ronroco, Venezuelan + Puerto Rican Cuatro, Jarana variants, Cavaquinho, Bandola, Vihuela, Tiple
Indian Classical
11
Sitar variants, Tanpura, Sarod, Surbahar, Veena, Rudra Veena, Dilruba, Esraj, Erhu, Sarangi
Lute
7
Renaissance Lute, Baroque Lute, Theorbo, Vihuela, Cittern, Oud Arabic, Oud Turkish
Orchestral Woodwind
2
Flute, Piccolo
Reed
11
Oboe, English Horn, Clarinet B♭ + A, Bass Clarinet, Bassoon, Contrabassoon, full Sax family
Brass
8
Trumpet/Cornet B♭, French Horn F, Trombone + Bass Trombone, Euphonium, Tuba B♭ + C

Reference pitch for
the 432 heads and
chamber musicians

SuperTuner ships with nine historical and modern presets, plus a free-form slider that runs from 400 to 480 Hz at 0.1 Hz precision. The reference affects everything: pitch detection, note naming, cents calculation, and the tone generator. Change it and the whole app retunes instantly.

  • A = 415 Hz Baroque
  • A = 416 Hz Half-step down
  • A = 430.54 Hz Scientific (C=256)
  • A = 432 Hz Verdi
  • A = 440 Hz ISO Standard
  • A = 441 Hz Boston Symphony
  • A = 442 Hz New York Phil.
  • A = 443 Hz European Concert
  • A = 444 Hz European Bright
  • Free 400–480 Hz

One layout,
every iOS device

A single codebase is hand-tuned for every form factor, from iPhone SE through Pro Max and iPad mini through iPad Pro, plus Split View. The app draws itself to fit.

At the core, a custom
note-detection algorithm

Most tuners run on one algorithm. The most common is YIN, which is fantastic for note detection but falls apart on the low end, leading to false or inaccurate readings. That's why your bass never tunes right through your guitarist's pedal.

On the other side there's autocorrelation, which can be slower but shines on the low end. We use both. YIN runs continuously and handles the vast majority of notes you'll play. When YIN detects a low note, it also has to pass an autocorrelation check. The check runs concurrently, so nothing slows down. The result is a tuner that is extremely accurate and sensitive across the full musical spectrum, while reliably rejecting room noise.

Frequency Range~27 Hz (A0) to ~1.5 kHz
Sample RateHardware-native (typically 48 kHz)
Analysis Window2,048 samples (~43 ms)
Hop Size512 samples (75% overlap)
UI Refresh20 Hz from audio thread
End-to-end Latency~33 ms reference-tone path
CPU (steady)~16% on iPhone XS-class
Memory~22 MB resident
Energy ImpactLow (Xcode metric)

For a deep dive on the math, tech specs, and design decisions, check out the Technical Documentation.

“I just want to tune my instrument, I don't care about all this nerd stuff!” That's fair. We think it's interesting, but we hear you. Moving on.

We don't hear you tuning

We don't want to.

SuperTuner is entirely private and free of ads. Audio is analyzed on your device and never leaves. We build with attention and care. We wouldn't dream of cluttering our surfaces with ads. We have no interest in data harvesting or surveillance capitalism. We build useful, beautiful tools. We hope you enjoy them.

SuperTuner is a PeaceDrone product.

PlatformiOS, iPhone & iPad (Universal)
Minimum iOSiOS 17.0
PermissionsMicrophone only
NetworkNone, fully offline
AnalyticsNone
Data CollectionNone
Third-Party SDKsNone
Audio ProcessingOn-device only
PublisherPeaceDrone LLC