Piano Tuner — Privacy Policy
Last updated: 2026-09-26
This privacy policy applies to the mobile app "Piano Tuner" on Android and iOS:
- Google Play: package com.simonj.pianotuner, developer "Global Utility App Maker"
- Apple App Store: bundle ID com.simonj.pianotuner, seller "Kyu-Hee Jang"
The app is developed and operated by Kyu-Hee Jang (Google Play developer name: Global Utility App Maker).
Contact: wkdrb2100@gmail.com
OVERVIEW
Piano Tuner does not require an account, and we do not sell personal information. The app listens to a piano string through the microphone, measures its pitch on the device, and stores your tuning measurements locally. It also uses Google services and an advertising mediation partner for analytics, crash reporting, remote configuration, and advertising.
MICROPHONE
The app asks for microphone permission only when you tap Listen on the Tune screen. Audio is analysed in memory on your device to find the pitch and the partials of the note you play. The app does not record, save, or upload audio. The microphone stops when you save a key, stop listening, leave the Tune screen, or send the app to the background. If you decline, the rest of the app still opens, but it cannot measure notes.
INFORMATION STORED ON YOUR DEVICE
The app stores up to 12 pianos. For each piano it keeps the name you give it, its A4 reference pitch, the date it was created, and one saved measurement per key (measured frequency, inharmonicity value when available, and the time it was saved). This is used to show which keys are in tune and to build the stretch curve.
The app may also store basic operating information such as app-use count, temporary feature-unlock state, and cached advertising or More Apps configuration.
The developer does not run a server that receives your measurements. The app reads developer-controlled advertising settings and a More Apps list from Google Cloud Firestore, but it does not upload your pianos or measurements.
ANALYTICS, CRASH REPORTING, AND ADS
Google Firebase Analytics may process limited app-usage and technical information, such as app launches, sessions, menu interactions, microphone start failures, app version, device type, and app-instance identifiers. When you save a key, an event records the key number and whether an inharmonicity value was included; it does not include piano names or measured frequencies.
Google Firebase Crashlytics may process crash reports and related technical information needed to diagnose app problems.
The app shows ads through Google AdMob. AdMob may also request ads from the InMobi mediation network. Google and InMobi may process advertising identifiers and device, app, consent, network, and ad-performance information to provide and measure ads, and may use an IP address to estimate an approximate location even though the app has no location permission.
PERMISSIONS AND ADVERTISING CHOICES
The only feature permission the app requests is the microphone, as described above. It does not request location, camera, contacts, photos, Bluetooth, health data, or notifications.
Where required (for example in the EEA and UK), Google's consent message (UMP) is shown first, and in those regions personalized advertising stays off unless your choice allows it. On iOS, the App Tracking Transparency prompt is shown only after that step and only when personalized advertising is allowed. If the consent message cannot be loaded, the app may still show non-personalized ads and does not ask for tracking permission. The app works whatever you choose.
You can change iOS tracking permission in Settings. Where Google requires it, the app menu shows "Privacy Choices", which reopens the consent message so you can change your advertising choice. The menu also links to this policy.
STORAGE AND YOUR CONTROL
You can clear all key measurements of a piano on the Keys screen, and rename or delete pianos on the Curve screen. You can also clear the app's data on Android or delete the app. Local data may be included in an Apple, Google, or device backup depending on your backup settings; uninstalling normally removes the active copy but may not remove an older backup.
Because we do not receive your measurements, we cannot delete them for you; the controls above remove them from your device. For questions about data processed by Google or InMobi, or to ask us for help with a privacy request, contact us at the address below.
Data processed by third parties is retained according to their service settings and policies, which require protection of personal data at least equivalent to this policy:
- Google Privacy Policy: https://policies.google.com/privacy
- Firebase privacy information: https://firebase.google.com/support/privacy
- Google advertising technologies: https://policies.google.com/technologies/ads
- InMobi Privacy Policy: https://www.inmobi.com/privacy-policy
SECURITY
Your saved data is kept in the app's private storage on your device, which the operating system protects from other apps; it is not separately encrypted by the app, so protect your device with a passcode. Apart from the limited analytics events described above, the app does not upload your saved data. Communication between the app and Google services and the ad mediation partner uses encrypted connections (HTTPS/TLS). No method of storage or transmission is completely secure, but we limit what the app collects to what is described in this policy.
IMPORTANT NOTICE
Readings depend on the microphone, room noise, and the instrument. The app is an aid for tuning; results should be confirmed by ear or by a piano technician, especially before changing string tension significantly.
CHILDREN
The app is not directed to children under 13, and we do not knowingly collect personal information from children.
CHANGES
We may update this policy if the app or its services change. The date above shows the latest revision.
CONTACT
Kyu-Hee Jang (Google Play developer: Global Utility App Maker)
Email: wkdrb2100@gmail.com