Platter Check — Privacy Policy
Last updated: 2026-10-03
This privacy policy applies to the mobile app "Platter Check" on Android and iOS:
- Google Play: package com.moon.turntable, developer "janey-moon"
- Apple App Store: bundle ID com.moon.turntable, seller "Heekyung Moon"
The app is developed and operated by Heekyung Moon (Google Play developer name: janey-moon).
Contact: ansgml2100@gmail.com
OVERVIEW
Platter Check does not require an account, and we do not sell personal information. The app uses the phone's gyroscope and accelerometer, and optionally the microphone, to measure turntable speed and wow and flutter, and it keeps a log of your turntables and saved measurements in the app's storage on your device. It also uses Google services for analytics, crash reporting, remote configuration, and advertising.
MICROPHONE AND MOTION SENSORS
Microphone: the app asks for microphone permission when you tap "Start listening" in the test-tone mode of the Wow tab and access has not been granted yet. While that measurement runs, the sound is analysed in memory to follow the frequency of a test tone played from a record. The audio is not recorded to a file, not saved, and not uploaded. The microphone is released when you tap Stop, leave the screen, or the app leaves the foreground. If you decline, the test-tone mode shows how to allow access in Settings; the gyroscope measurements and the strobe disc still work.
Motion sensors: the gyroscope (and, on the Speed screen, the accelerometer to detect vibration or sliding) is read only while a speed, wow, or calibration measurement is running on screen, and it stops when you leave the screen or the app. These sensors do not need a system permission. Readings are processed in memory; only summary results are kept, when you tap "Save to log", plus the latest calibration result, which is saved when a calibration completes. The screen is kept awake while a speed or wow measurement runs.
INFORMATION STORED ON YOUR DEVICE
Log: up to 50 turntables and up to 2,000 measurements. A turntable has the name you give it and an optional cartridge name and the time it was added. A measurement has its turntable, the time, its type (speed, wow by gyroscope, or wow by test tone), the target speed, an optional note, and the computed results: average speed, deviation from target, repeatability and number of revolutions, peak, 2-sigma and RMS deviation, once-per-revolution amount, duration, and for the test-tone mode the reference and measured tone frequency and the speed offset.
Settings: the selected speed (including a custom speed), mains frequency (50 or 60 Hz), reference tone (3150 or 3000 Hz), wow mode, the last turntable used, and the latest gyroscope calibration (offset, noise level, sample count, and time).
Copies: if the saved log is damaged and cannot be parsed, or before a restore replaces it, a copy of the previous log is kept in the app's storage so it is not silently lost. These copies are not shown in the app.
The app also stores basic operating information: an app-use count, whether the review prompt was shown, the times of recent full-screen ads, cached advertising configuration, and a cached More Apps list (refreshed after 24 hours).
The developer does not run a server that receives your log. The app reads developer-controlled advertising settings and a More Apps list (including app icons loaded from web addresses) from Google Cloud Firestore; it does not write your log, notes, or measurements there.
ANALYTICS, CRASH REPORTING, AND ADS
Google Firebase Analytics may process limited app-usage and technical information, such as app launches, sessions, the app-use count, tab, screen, and menu opens (including the privacy policy and More Apps items), review-prompt events, the tracking-prompt answer, an app-open ad shown at launch, ad revenue amounts (ad format, value, currency, and precision), app version, device type, and app-instance identifiers. Events about saving a measurement, calibrating, exporting, or restoring the log, or about a saved log that could not be read, record only the event and, for a saved measurement, its type. They do not include turntable or cartridge names, notes, or measurement values.
Google Firebase Crashlytics may process crash reports and related technical information needed to diagnose app problems.
The app shows ads through Google AdMob: a banner on the Log screen, a native ad in the exit dialog, an app-open ad at launch or when you return to the app, and an interstitial ad that may follow a saved measurement. The app does not start app-open or interstitial ads while a speed, wow, or calibration measurement is running, or while the export, PDF, or share sheet is open. Google 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. The app does not request location permission.
PERMISSIONS AND ADVERTISING CHOICES
Feature permissions: microphone (for the test-tone mode only). The app also uses internet access and vibration (short haptics when a measurement is saved and when you switch tabs). It does not request location, camera, contacts, photos, Bluetooth, health data, or notification permission.
When the app starts, Google's consent message (UMP) is checked first and shown where required (for example in the EEA and UK). Personalized ads are requested only when that result allows them; otherwise ads are non-personalized, or are not requested if Google's completed consent check does not allow ad requests. On iOS, the App Tracking Transparency prompt is shown only after that step and only when personalized advertising is allowed. If tracking is not allowed, the IDFA is not available to the app or its ad partners. If the consent check fails with an error at launch, the app does not show the tracking prompt at that time and requests non-personalized ads; if you later use "Privacy choices" in the menu, your new choice applies and the tracking prompt may then be shown.
Where Google indicates that privacy options are required, the app menu shows "Privacy choices", which reopens the consent message so you can change your advertising choice. You can change microphone and tracking permissions in your device Settings at any time. The app works whatever you choose.
STORAGE AND YOUR CONTROL
On the Log screen you can delete a single measurement, or delete a turntable together with all of its measurements (an Undo button appears for a few seconds). The 50-turntable and 2,000-measurement limits are enforced by the app, including when you undo a deletion; older entries are not removed automatically. Settings, calibration, and the copies described above have no separate delete button; clearing the app's data on Android or deleting the app removes them from the app's storage.
"Export log" writes a JSON file with all turntables, measurements, and notes to the app's cache folder and opens the share sheet; where you send it is your choice, and the file may remain in the cache until the system clears it or you clear the app's data. "Create PDF" on the Strobe disc screen makes a PDF of the disc pattern and instructions in temporary storage. "Restore log" replaces the log with text you paste.
Android may include app data in device backups because the app does not turn off Android backup, and on iOS app data may be included in your device or cloud backups. Uninstalling normally removes the active copy but may not remove an older backup.
Because we do not receive your log, we cannot delete it for you; use the controls above. For questions about data processed by Google, or to ask for help with a privacy request, contact us at the address below.
We use these services under their applicable terms, and we ensure that third-party service providers with whom we share user data provide the same or equal protection of that data as stated in this policy. Data processed by Google is retained according to its service settings and policies:
- 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
SECURITY
Your log is kept in the app's private storage, 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 log; it is sent elsewhere only if you export and share it. Communication between the app and Google services uses encrypted connections (HTTPS/TLS). No method of storage or transmission is completely secure, but we limit what the app processes to what is described in this policy.
IMPORTANT NOTICE
Speed, wow and flutter, and tone-frequency readings are estimates from phone sensors and the phone microphone. These are approximations, not a substitute for calibrated test equipment: the gyroscope's scale is not calibrated, readings include sensor noise, and the test-tone result assumes the record's tone is exact. Check absolute speed with a strobe disc or another reference before adjusting your turntable. Handle the turntable carefully: place the phone gently on a still record or mat, keep it clear of the tonearm and stylus, and lift it off before cueing the stylus.
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
Heekyung Moon (Google Play developer: janey-moon)
Email: ansgml2100@gmail.com