Key Shift — Privacy Policy
Last updated: 2026-10-03
This privacy policy applies to the mobile app "Key Shift" on Android and iOS:
- Google Play: package com.moon.songkey, developer "janey-moon"
- Apple App Store: bundle ID com.moon.songkey, seller "Heekyung Moon"
The app is developed and operated by Heekyung Moon (Google Play developer name: janey-moon).
Contact: ansgml2100@gmail.com
OVERVIEW
Key Shift does not require an account, and we do not sell personal information. The app plays songs you choose from your device in a different key or tempo for practice, with A-B loops, setlists, and export of the shifted audio. Your songs and practice settings are kept in the app's storage on your device. The app also uses Google services for analytics, crash reporting, remote configuration, and advertising.
AUDIO FILES, PLAYBACK, AND NOTIFICATIONS
The app does not use the microphone and does not record audio. It does not ask for access to your music library, photos, or device storage. You add a song by choosing an audio or video file in the system file picker; only the file you pick is opened. The app moves a copy of that file into its own documents folder so it can play it later. For a video, only its audio is used; on iOS, when a file (such as a video) cannot be played directly, its extracted audio is also kept in the app's cache folder. Song files are not uploaded to the developer and are not included in analytics.
When a song without a key and tempo estimate is opened, or when you tap to analyse it again, the app decodes about 30 seconds of it in memory to estimate its key and tempo. The audio excerpt is not saved; only the result (the estimated key and tempo and which part was analysed) is stored with the song.
While a song is loaded or playing, its name is shown in the system media controls (for example the lock screen and, on Android, the playback notification). On Android 13 and later, while background playback is on, the app asks for notification permission the first time you tap play. If you decline, playback pauses when you leave the app, and every other feature still works. You can turn background playback off in Settings.
INFORMATION STORED ON YOUR DEVICE
The app stores a library of up to 500 songs. Each song record contains its name (taken from the file name unless you rename it), the name of the stored audio file, its length and number of channels, when it was added and last opened, the key and tempo estimate, and your practice settings: semitone and cent shift, tempo, A-B loop points and loop on/off, count-in, the loop tempo trainer, vocal reduction, capo, and any key or tempo you set yourself.
It also stores up to 100 setlists (a name and up to 200 songs each), your note-name style, the background-playback setting, whether notification permission was already asked, and a list of song files that are kept safe after a storage error. If saved data cannot be read, a copy of it is kept on the device so it is not silently lost. The app may also store basic operating information such as app-use count, whether the review prompt was shown, the times of recent full-screen ads, and cached advertising or More Apps configuration.
The developer does not run a server that receives your songs or settings. The app reads developer-controlled advertising settings and a More Apps list (whose app icons are loaded from the internet) from Google Cloud Firestore. It does not write to Firestore and does not upload your songs, song names, or practice settings.
ANALYTICS, CRASH REPORTING, AND ADS
Google Firebase Analytics may process limited app-usage and technical information, such as app launches, sessions and their count, tab, page and menu opens, review prompts, More Apps and privacy-policy opens, splash ads shown, your answer to the iOS tracking prompt, app version, device type, and app-instance identifiers. Events about songs record only the action (adding, opening or deleting a song, setting a loop, correcting a key, starting or finishing an export) and simple values: the semitone shift and tempo factor when you play or export, and whether the key and tempo estimate succeeded. They do not include song names, file names, or the detected key. Ad revenue events record the ad format and the value, currency, and precision reported by the ad service.
Google Firebase Crashlytics may process crash reports and related technical information needed to diagnose app problems.
The app shows banner, app-open, interstitial, and native ads through Google AdMob. 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. Banner ads appear only on the Library screen. The app does not start app-open or interstitial ads while a song is playing or being exported, or while the file picker or share sheet is in use.
PERMISSIONS AND ADVERTISING CHOICES
Feature permissions: notifications (Android 13 and later), used for background playback. On Android the app also uses standard internet, vibration, foreground-service, and wake-lock permissions for network access, haptic feedback, and playback with the screen off. The app does not request microphone, camera, location, contacts, photos, media library, or storage permissions.
Where required (for example in the EEA and UK), Google's consent message (UMP) is shown first, and 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 tracking is not allowed, the IDFA is not available to the app or its ad partners. If the consent step fails with an error when the app starts, the app may still request ads, but only non-personalized ones, and does not show the tracking prompt at that time; if you later use "Privacy choices" in the menu, your new choice applies and the tracking prompt may then be shown. The app works whatever you choose.
You can change notification and tracking permissions in your device Settings at any time. Where Google requires it, the app menu shows "Privacy choices", which reopens the consent message so you can change your advertising choice. This policy is published at https://sites.google.com/view/songkeysss.
STORAGE AND YOUR CONTROL
On the Library screen, open a song's options to rename or delete it. Deleting removes the song from the library and from every setlist and, after a few seconds in which you can undo, deletes the app's copy of its audio file. If the app is closed before then, the copy is removed the next time the app starts, unless it is on the list of files kept safe after a storage error. On the Setlists screen you can remove songs from a setlist or delete a setlist.
Exported audio files (.m4a, named after the song with its new key and tempo) are kept in the app's exports folder. When you start a new export, older exports are deleted so that at most five are kept; there is no separate delete button, and deleting a song does not delete its exports. On iOS, audio extracted from a video or other file stays in the app's cache folder after the song is deleted. Backups saved from Settings (Backup) are files containing your song records (names, stored file names, lengths, channel counts, dates added and last opened, practice settings, and key and tempo estimates) and setlists, but not the audio. A copy is written to the app's cache folder before the share sheet opens and may remain there until the system clears it. Files you share or save elsewhere are outside the app's control.
To remove all of the app's data, clear the app's storage on Android or delete the app. Local data, including song copies and exports, 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 songs or settings, we cannot delete them for you; the controls above remove them from the app. For questions about data processed by Google, or to ask us for help with a privacy request, contact us at the address below.
Data processed by Google is retained according to Google's policies and the service settings chosen by the developer. 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.
- 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 songs and settings are kept in the app's private storage on your device, which the operating system protects from other apps; they are 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 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
The key and tempo shown for a song are automated estimates from a short excerpt and may be wrong, for example with unclear harmony or half or double time. Check them by ear and correct them in the app if needed. Vocal reduction results depend on the recording. You are responsible for having the rights to the music you add, change, export, or share with the app.
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