Kawaii Keys: Privacy Policy
Last updated: 5 November 2026
Kawaii Keys ("the app") is made by Bui Dinh Dan ("we", "us"). This policy explains what information the app uses, why, and the choices you have. It covers the iOS and Android apps.
Summary
- No accounts and no sign-in. We never ask for your name, email, contacts, photos or precise location.
- The microphone is used only to hear which notes you play on your piano. Sound is analysed on your device and is never recorded, stored or sent anywhere.
- Your progress, settings and imported song files are saved only on your device.
- The app shows optional rewarded ads and an occasional full-screen ad through Google AdMob. Kawaii Keys Plus members see no ads.
- Optional purchases (Kawaii Keys Plus, Melody Star packs) are handled entirely by the App Store or Google Play.
- The app has no server of its own and no analytics SDK. We do not sell your information.
Data Collection & Analytics
Microphone
When you choose "Acoustic Piano (Mic)" as your input, the app listens through the microphone during lessons, the setup test, Ear Quest, Note Flashcards and Free Play, so it can tell which key you pressed. The sound is turned into note names in your device's memory and immediately discarded. Nothing is recorded, saved or uploaded, and the microphone is off on every other screen. You can switch to the touch keys at any time, or turn off microphone access in your device settings.
Stored on your device
The following are stored only on your device and never sent to us. Deleting the app deletes them.
- Your lesson and song stars, scores, practice streak, XP, trophies and Melody Stars.
- Costumes, settings and your measured room noise level.
- Songs you import (MIDI or MusicXML files you add through the Files app or your system file picker).
Purchases
Kawaii Keys Plus (monthly or yearly subscription, or a one-time lifetime unlock) and Melody Star packs are sold through the App Store or Google Play. The store processes the payment. We never see your name or payment details. The app only asks the store which products this store account owns, on your device, to unlock Plus.
Advertising
The app shows optional rewarded ads:
- double XP after a song,
- double Melody Stars after a Rhythm Arcade run,
- an extra heart in Ear Quest.
It also shows an occasional full-screen ad between sessions, never during play. Ads are delivered by Google AdMob. To show and measure ads, Google may collect device and advertising identifiers, approximate location derived from your IP address, ad interactions and diagnostic data. Ads are never required to learn or play, and Kawaii Keys Plus removes them.
Analytics
The app does not use Google Analytics, Firebase Analytics or any other analytics SDK.
Notifications
If you allow practice reminders, the app schedules local notifications on your device. They are created on the device; no push service or server is involved.
Third-Party SDK Disclosures
| Service | What it receives | Why | Policy |
|---|---|---|---|
| Google AdMob | Device and advertising identifiers (IDFA on iOS only if you allow tracking), IP address (used to estimate your region), device and app information, ad interactions and diagnostics. | To show and measure ads and prevent fraud. | Privacy policy |
| Apple App Store / Google Play | Download and purchase records handled by the store. | To distribute the app and process optional purchases. | Apple, Google |
Your choices:
- EEA, UK and Switzerland: the app asks for your consent through Google's consent form before any ad loads. You can change it any time under Settings → Ad Privacy.
- iOS: the app asks for permission before using your advertising identifier (App Tracking Transparency). You can change this in iOS Settings → Privacy & Security → Tracking.
- Android: you can reset or delete your advertising ID in your device settings.
Children's Privacy (COPPA)
The app is not directed at children under 13, and we do not knowingly collect personal information from children under 13, in line with the U.S. Children's Online Privacy Protection Act (COPPA) and similar laws.
- Ads are configured as not child-directed and limited to content rated PG.
- A grown-up check appears before any purchase.
If you are a parent or guardian and believe your child has provided personal information through the app, email [email protected] and we will delete it.
Account & Data Deletion
The app has no accounts, so there is no account to delete. To delete your data:
- On your device: uninstall the app. This removes your progress, settings and imported songs.
- Subscriptions: manage or cancel them in your App Store or Google Play account settings. Deleting the app does not cancel a subscription.
- Advertising data: data collected by Google AdMob is controlled by Google. You can reset your advertising ID in your device settings or manage it at https://myadcenter.google.com.
Security
Ad and store traffic uses encrypted connections (HTTPS/TLS). Microphone audio never leaves the device.
Changes
If this policy changes, we will update this page and the date at the top.
Contact
Bui Dinh Dan
Email: [email protected]