Centerline Google Play

Available now on Android

Every note has a center.

Centerline gives each pluck a large, steady read. Choose the display that makes flat, sharp, and in tune easiest to see.

Get it onGoogle Play See how it works

Free standard tuning US $3.99 one-time unlock

Centerline's Guitar display showing the high E string in tune
01No adsNothing between you and the meter
02No accountOpen it and start tuning
03Works offlineNo internet permission
04One priceNo recurring subscription

The quick check

Ready before the amp warms up.

Centerline listens as soon as it opens and finds the closest guitar string for you. The direction stays obvious from across the room: blue means flat, orange means sharp, and green is the center.

  • AutomaticString detection
  • VisibleClear turn direction
  • SteadyA readable decay tail

Four displays, one reading

Read pitch your way.

Every display uses the same pitch engine. Pick the view that makes the live reading easiest for you to follow.

01

Simple

The note, the direction, and one centerline. Nothing else on the stage.

Guitar display with automatic string detection and the high E string centered
02

Guitar

See the whole instrument and let Centerline identify the string, or tap one to lock it.

Strobe display showing a B string that is 15 cents sharp
03

Strobe

Watch the bars drift while the string is off pitch. They settle when the note does.

All Strings display showing tuning progress across six strings
04

All strings

Work across all six strings and keep the full tuning in view as you go.

Centerline Complete

A tuner isn't a subscription.

Standard tuning, automatic string detection, and all four displays are free. Pay once only if you want alternate tunings and reference-pitch calibration.

No trial clock. No recurring charge.

Complete unlock
$3.99USD · once
  • Drop D
  • Half step down
  • D standard
  • DADGAD
  • Open G
  • A4 · 432–446 Hz
Download free onGoogle Play

Google Play may show a localized price.

Private by construction

Your microphone never becomes a file.

Pitch is analyzed live on your phone, then discarded. The Android and iOS apps have no account, advertising, or analytics. They contain no networking code.

This website separately uses self-hosted Umami to measure visits and selected interactions. It uses no cookies or cross-site tracking and respects Do Not Track.

Read the privacy policy
01MicrophoneLive audio
02On devicePitch only
03DisplayThen discarded
Internet permission
Not requested
Audio retention
None
App analytics
None
Account
Not required

Free on Android

Centerline is ready when your guitar isn't.

Get it onGoogle Play