Effective date: April 22, 2026
This Privacy Policy describes how Yomabi ("the App", "we", "us") collects, uses, and protects information when you use our mobile applications for Android and iOS. Yomabi is a Japanese dictionary and learning app that provides dictionary lookups, OCR-based text recognition, flashcard-based spaced repetition, and other language learning tools.
In short: Yomabi is designed with privacy in mind. All your personal study data stays on your device. Analytics are disabled by default and require your explicit opt-in. No user accounts or server-side storage exist.
The following data is stored entirely on your device and is never transmitted to any server:
This data is stored in on-device databases and local preference storage (Room / DataStore on Android, equivalent local storage on iOS). You have full control over this data and can delete it at any time from within the app, by clearing the app's data in your device settings (Android), or by uninstalling the app.
Yomabi integrates Firebase Analytics to help us understand how the app is used and to improve the experience. Analytics collection is disabled by default. On first launch, a consent dialog asks whether you would like to enable anonymous usage analytics. You can change this choice at any time in the app's Settings.
When enabled, Firebase Analytics collects:
This data is anonymous and aggregated. It does not include your search queries, flashcard content, or any personal study data.
Yomabi uses Firebase Crashlytics to collect crash reports and stability data so we can identify and fix bugs. Crashlytics runs under our legitimate interest (GDPR Art. 6(1)(f)) in maintaining the app's stability and is not gated by the usage analytics toggle.
Crashlytics collects:
Crash data does not include any of your personal study content, search queries, or flashcard data. To object to this processing under Art. 21 GDPR, please contact us using the address in Section 10; you can also clear the app's data to reset the FID or uninstall the app to stop all future crash reports.
Yomabi uses Firebase Remote Config to adjust certain non-personal app parameters without requiring a new app release — for example, the daily free OCR lookup limit, the number of rewarded ads available per day, whether the Plus upgrade prompt is shown, and the minimum supported app version.
Remote Config fetches run at app start on the legal basis of our legitimate interest (GDPR Art. 6(1)(f)) in being able to operate and tune the app's configuration without shipping a new release for every change. Each fetch transmits a Firebase Installation ID (see Section 1.5) and basic app / SDK metadata (package name, app version, locale) to Google. No behavioural analytics, no search queries, and no personal study content are involved. To object under Art. 21 GDPR, please contact us using the address in Section 10; you can also clear the app's data to reset the FID or uninstall the app to stop all future requests.
Any Firebase service that makes a network request — Crashlytics and Remote Config (always on under legitimate interest) and Analytics (only after you opt in) — transmits a Firebase Installation ID (FID). The FID is a randomly generated identifier that represents your installation of Yomabi. Google uses it to associate requests from the same installation across the Firebase services that are active.
The FID is reset if you clear the app's data or reinstall Yomabi. It is not linked to your Google account and is not shared with any third party other than Google.
Yomabi displays rewarded video ads (via Google AdMob) that provide bonus OCR lookups. The AdMob SDK may collect certain data in accordance with Google's advertising policies, including:
Consent (EEA / UK / Switzerland). In the European Economic Area, the United Kingdom, and Switzerland, Google's User Messaging Platform (UMP) shows a consent dialog on first launch that lets you choose whether Google and its ad partners may process your data for personalized advertising and related purposes. If you decline, non-personalized ads are shown instead. You can re-open this consent form at any time via Settings → Ad Privacy Settings.
App Tracking Transparency (iOS). On iOS 14.5 and later, before any ad-tracking identifier (IDFA) is read, the operating system shows a system-level “Allow Tracking?” prompt (App Tracking Transparency). If you choose “Ask App Not to Track”, the IDFA is not shared and non-personalized ads are shown.
US state privacy laws (CCPA / CPRA and similar). Residents of California and other US states with comparable privacy laws may use the same UMP consent form to opt out of the sale or sharing of personal information for targeted advertising. Selecting the “Do not sell or share my personal information” option in that form instructs Google and its ad partners to apply the Global Privacy Control / US opt-out signal. Yomabi itself does not sell personal information.
Data collected by AdMob is processed by Google. Please refer to Google's Privacy Policy for details on how Google handles this information.
Yomabi offers in-app purchases (Pro upgrade and optional tips) through the platform's billing system — Google Play Billing on Android and Apple In-App Purchase (StoreKit) on iOS. Purchase transactions are handled by Google or Apple respectively. Purchase tokens or transaction identifiers are stored locally on your device only. We do not operate any server that processes or stores payment information.
If you tap Send Feedback in Settings and choose to submit a bug report, the following is transmitted to a Google Apps Script endpoint we control:
Bug reports are only sent when you explicitly tap the submit button. The payload is signed with HMAC-SHA256 before transmission so we can reject forged submissions. The random per-install identifier resets when you clear app data or reinstall Yomabi.
| Permission | Purpose | Data Handling |
|---|---|---|
| Camera | OCR text recognition from camera or photos | All images are processed entirely on-device using local OCR models (PaddleOCR on Android, Apple Vision / ML Kit on iOS). No images are sent to any server. |
| Microphone / Speech Recognition | Voice search (speech-to-text) | Audio is processed on-device via the platform speech recognizer (Android SpeechRecognizer / iOS SFSpeechRecognizer). No audio is transmitted to Yomabi's servers. |
| Photo Library | Attaching images to flashcards; importing saved screenshots for OCR | Images remain on-device. Nothing is uploaded. |
| App Tracking Transparency (iOS) | Permission to read the IDFA for personalized ads | See Section 1.6. Declining keeps ads fully functional (non-personalized). |
Yomabi uses the following third-party services. Each service has its own privacy policy governing data it collects:
Beyond these services, Yomabi does not share data with any other third-party services, advertisers, or data brokers.
All user study data (search history, favorites, flashcards, SRS progress) is stored locally on your device and is retained until you choose to delete it. You can delete your data at any time by:
For data collected by Firebase Analytics and Crashlytics, Google's standard data retention policies apply. Firebase Analytics data is retained for up to 14 months by default. Crashlytics data is retained for 90 days.
Bug report submissions are retained in a private Google Sheet for as long as we consider them useful for diagnosing the reported issue, and may be deleted on request using the address in Section 10.
If you are located in the European Economic Area (EEA), the United Kingdom, or Switzerland, you have the following rights under the General Data Protection Regulation (GDPR) / UK GDPR:
Data controller for GDPR purposes: Boris Tokic. Contact details in Section 10.
Legal bases (summary):
If you are a resident of California, Colorado, Connecticut, Virginia, Utah, or another US state with a comparable consumer privacy law, you have the following rights:
How to exercise opt-out. In the AdMob consent form (Settings → Ad Privacy Settings) select the “Do not sell or share my personal information” option. We also honor the Global Privacy Control (GPC) signal where it is available.
Do Not Sell My Personal Information. Yomabi itself does not sell personal information. AdMob may share device identifiers with ad partners for personalized advertising; opting out via the UMP form stops this sharing.
To exercise any of the above rights, contact us using the address in Section 10.
Yomabi is not directed at children under the age of 13. We do not knowingly collect personal information from children under 13. If you are a parent or guardian and believe your child has provided data through the app, please contact us and we will take steps to address the situation.
Because Yomabi stores all user data locally on your device, the security of your data depends on your device's own security measures (screen lock, encryption, etc.). We recommend keeping your device's operating system up to date and using a secure lock screen.
Data transmitted to Firebase, AdMob, and our bug-report endpoint is encrypted in transit using industry-standard protocols (TLS/SSL). Bug-report submissions are additionally signed with HMAC-SHA256.
We may update this Privacy Policy from time to time. When we do, we will revise the "Effective date" at the top of this page. We encourage you to review this Privacy Policy periodically to stay informed about how we protect your information. Continued use of the app after changes constitutes acceptance of the updated policy.
If you have any questions or concerns about this Privacy Policy or Yomabi's data practices, or to exercise any of the rights described above, please contact us at: