METRO X Digital Tuner — Real-Time Pitch Detection for All Instruments

A real-time tuner accurate to the cent, built for piano, violin, viola, cello, guitar, brass, woodwinds, and the rest of the orchestra. No extra hardware, no separate app — bundled inside METRO X for iPhone and iPad.

Why most tuner apps fall short

Generic tuner apps are designed for one thing: tuning a six-string guitar to standard tuning. They guess at the note, smooth the readout so you don't see micro-fluctuations, and freak out the moment you give them a violin double-stop or a French horn at fortissimo. The METRO X tuner is built for serious musicians: it tracks pitch frame-by-frame, doesn't smooth away the truth, and stays stable on every orchestral instrument we tested.

What the tuner does

  • Cent-precision pitch detection. Read your pitch in cents above or below concert pitch. Spot a 5-cent flat tendency on your G string before it becomes a habit.
  • Works for every instrument. Piano, violin, viola, cello, double bass, guitar, drums, brass, woodwinds, and voice. The detection algorithm is instrument-agnostic.
  • Stability indicator. A visual stability meter shows when your pitch has settled, so you know when to stop adjusting and trust the readout.
  • Concert pitch reference. Default to A=440 Hz or change to any reference your ensemble uses (A=441, A=442, A=415 for baroque practice).
  • Quiet-room friendly. Sensitive enough to read soft pizzicato or the breath tone on a flute, robust enough to ignore room noise.
  • Bundled with the metronome. Tuner and metronome live in the same app, so you can intonate a long tone against a stable click without switching apps.

How to use the METRO X tuner

  1. Grant microphone access. On first launch, allow METRO X to use your device microphone.
  2. Play a single sustained note. Hold a long, steady note. The note name appears immediately and the cent display settles within a second.
  3. Watch the cent display. The note name tells you what you're playing; the cents number tells you how to adjust. Aim for the green zero.
  4. Train your ear, then play without it. Use the tuner to map your instrument's tendencies, then practice playing those intervals without the tuner.

Related

Pair the tuner with the metronome for long-tone intonation practice. See the METRO X metronome →

Get METRO X free on the App Store →