YomuLens legal
Privacy Policy
Effective date: September 4, 2026
This Privacy Policy applies to the YomuLens mobile application and related services (“YomuLens”, “the Application”, “we”, “us”, or “the Service Provider”).
The Application is operated by a French micro-entrepreneur. Contact details for privacy questions and data protection requests are provided in the Contact section at the end of this Policy.
Summary
YomuLens does not require an account and does not ask you to provide your name, email address, age, gender, phone number, postal address, or login credentials.
The app is designed primarily to work locally on your device. However, some features rely on third-party services, including model file hosting, translation, web browsing, and advertising services. When you use those features, certain data may be processed by those third parties as described below.
Information Processed by the Application
YomuLens may process the following categories of information:
- Imported files and content, such as EPUB, PDF, CBZ, images, or text that you choose to open in the app.
- Reading and learning data stored locally on your device, such as library entries, reading progress, vocabulary, study progress, favorites, and app settings.
- Detailed study-event history stored locally on your device, including SRS review results and stage changes, drawing-practice outcomes, assistance usage, attempt numbers, and timezone-safe timestamps.
- Statistics derived from local study history, such as activity, streaks, accuracy, retention, mastery, projected review workload, and weak-Kanji rankings.
- Text or image crops selected for OCR, translation, or AI-assisted features.
- Network request information related to downloading OCR model files, such as IP address, device network information, requested file URL, and request time, as processed by the model file hosting provider.
- API keys that you choose to enter for optional third-party translation services.
- Advertising-related data processed by Google Mobile Ads and its partners.
- Local reminder and notification information, such as reminder settings, due review counts, recent saved-word activity, and reading activity used to schedule optional notifications.
YomuLens does not create user accounts and does not directly collect account profile information such as your name, email address, age, gender, phone number, or postal address.
Local Storage
YomuLens stores certain information locally on your device to provide its features, including:
- Your library and imported content metadata.
- Reading progress.
- Vocabulary and study progress.
- Study-event history and statistics used to provide progress insights, SRS scheduling, targeted practice, and study reminders.
- Favorites and browsing/session information.
- App settings.
- Reminder and notification settings, including reminder time, quiet hours, and whether specific reminder types are enabled.
- User-provided API keys for optional translation services.
User-provided API keys are stored using secure storage where supported by the operating system. Backup exports do not include API keys.
Uninstalling the app may remove locally stored app data depending on your device and operating system behavior.
The app may also cache webpage images, reader images, cover images, and pronunciation audio locally to improve performance.
Study-event history and derived statistics are processed on your device and are not sent to YomuLens-operated servers. They leave the device only when you choose a feature that exports them, such as a manual or automatic backup to a folder you select.
Imported Content
You may import books, EPUB, CBZ, PDFs, archives, images, or other files into YomuLens. These files are processed to provide reading, OCR, vocabulary, and study features.
YomuLens can access files or folders that you explicitly select to discover and import supported books. This access may persist until you disconnect the folder or revoke access through Android; filenames and book contents used by this import feature are processed locally and are not uploaded.
Most imported content is processed locally on your device. The accurate manga OCR engine runs on-device after downloading and verifying its model files. If you use cloud translation, browser reading, or AI-assisted features, selected text or relevant excerpts may be sent to external services needed to provide those features.
OCR, Translation, and AI Features
YomuLens includes OCR, translation, and AI-assisted features. Depending on the feature and engine selected, data may be processed locally or sent to third-party services.
The accurate manga OCR engine downloads model files from Cloudflare R2/CDN, verifies them against pinned SHA-256 hashes, and then runs locally on your device. Cloudflare may process standard network request data when those model files are downloaded, but the local OCR process does not send your image crops to Cloudflare.
If you select Cloudflare AI translation, the text you ask to translate is sent to a YomuLens-operated Cloudflare Worker, which forwards the text to Cloudflare Workers AI for translation using an AI model available through Cloudflare. The mobile app does not include Cloudflare account tokens or credentials. If the Cloudflare AI quota or rate limit is reached, YomuLens may fall back to on-device Google ML Kit translation.
These services may include:
- Cloudflare, for hosting and delivering OCR model files and for optional Cloudflare AI translation.
- Mistral, if you choose to enable Mistral translation with your own API key.
- Google services, including Google ML Kit for on-device OCR and translation where available.
When using cloud translation or example generation, the data sent may include selected text, words, readings, or prompts needed to generate results.
If you generate example sentences or translations using an external provider, the relevant word, reading, text, or prompt may be sent to that provider.
YomuLens does not use this data to create user profiles. However, third-party providers may process data according to their own privacy policies and terms.
User-Provided API Keys
Optional Mistral translation requires you to provide your own API key. If you choose to enter a key:
- The key is stored locally using secure storage where supported.
- The key is used only to make requests to the service you selected.
- The key is not included in backup exports.
- You are responsible for managing your own API key, including costs, quotas, revocation, and provider account settings.
YomuLens cannot prevent third-party providers from applying their own usage limits, billing rules, or data processing practices.
Advertising
YomuLens uses Google Mobile Ads to display ads.
Google and its partners may collect or process information such as device identifiers, advertising identifiers, IP address, app interaction data, diagnostics, approximate location inferred from IP address, and other information as described in Google’s policies.
Where required by law, YomuLens will request consent before using personal data for personalized ads or before accessing local storage for advertising purposes. You may be offered privacy choices through a consent message, and where required, you will be able to change or withdraw your choices later.
Google’s privacy information is available here:
- Google Privacy Policy: https://policies.google.com/privacy
- Google Partner Sites Policy: https://policies.google.com/technologies/partner-sites
- AdMob information: https://support.google.com/admob/
Cookies and Similar Technologies
The Application itself does not use traditional website cookies for account login or analytics.
However, third-party SDKs and services, including advertising services and webpages opened in the built-in browser, may use cookies, local storage, SDK identifiers, or similar technologies.
Where required by law, YomuLens will request consent before using non-essential tracking technologies for advertising or similar purposes.
Web Browsing Features
YomuLens includes a built-in browser and reader mode features. When you open websites through the app, those websites may collect data according to their own privacy policies.
YomuLens does not control third-party websites. Websites opened in the browser may use cookies, analytics, ads, login systems, or other third-party technologies.
Permissions
YomuLens may request device permissions needed for app functionality, including:
- Internet access, for browsing, OCR, translation, ads, and external services.
- Access to files or folders you explicitly select through the operating system, for importing images and books or storing optional backups.
- Microphone access, for speech or pronunciation-related features.
- Notification permission, for optional study, saved-word, and continue-reading reminders.
When you use speaking practice features, your microphone input is processed by the device or operating system speech recognition service to convert speech into text. YomuLens uses the recognized text to check your answer and does not create user voice profiles.
For pronunciation features, YomuLens may use on-device text-to-speech where available. If on-device speech audio is unavailable, the app may request pronunciation audio from an external audio provider and cache the audio file locally on your device.
If you enable reminders, YomuLens may schedule local notifications based on your app settings, vocabulary review status, recently saved words, and recent reading activity. Notification content may appear on your device lock screen or notification center, depending on your device settings. Reminders can be changed or disabled in the app or through your device settings.
Permissions are used only to provide the related app features.
Legal Bases for Processing
Where the GDPR applies, we rely on one or more of the following legal bases:
- Contract performance: to provide the app features you request.
- Consent: where required, such as for personalized advertising or optional processing.
- Legitimate interests: to maintain app functionality, security, and reliability.
- Legal obligation: where processing is necessary to comply with applicable laws.
You may withdraw consent at any time where processing is based on consent.
Third-Party Services
YomuLens may use third-party services that process data according to their own privacy policies, including:
- Google Play Services
- Google Mobile Ads / AdMob
- Google ML Kit, for on-device OCR and translation where available
- Cloudflare, for OCR model file hosting and delivery, and for optional Cloudflare Workers AI translation
- Device or operating system speech recognition and text-to-speech services
- Mistral, if enabled by the user
- LanguagePod101 / Innovative Language, for pronunciation audio fallback where used
- Websites opened through the built-in browser
These third parties may process data outside your country or region.
International Data Transfers
Some third-party service providers may process data outside the European Economic Area, the United Kingdom, Switzerland, or your country of residence.
Where required by law, appropriate safeguards will be used, such as adequacy decisions, Standard Contractual Clauses, consent, or other lawful transfer mechanisms.
Data Retention
YomuLens stores local app data for as long as the app remains installed or until you delete the data through app or device controls.
Deleting an individual vocabulary item may not delete its historical study events. Historical events may remain available for lifetime totals, but removed vocabulary is excluded from actionable weak-Kanji and practice recommendations.
Data processed by third-party services is retained according to those providers’ own policies.
If you contact us by email, we may retain your message for as long as necessary to respond to your request, handle support, and comply with legal obligations.
Data Deletion
You can delete locally stored app data by using available app controls, deleting imported content, clearing app data through your device settings, or uninstalling the app.
YomuLens allows you to create local backup export files manually. On supported devices, you may also enable an optional automatic weekly backup. Automatic backups are checked when YomuLens opens after at least seven days and are written to a folder you select through the operating system. YomuLens keeps the five newest automatic backup files that it created in that folder.
Manual and automatic backup files may include vocabulary data, saved words, readings, definitions, example sentences, detailed study-event history, and manually saved website bookmarks. Study-event history may include timestamps, SRS review results and stage changes, drawing-practice outcomes, assistance usage, and attempt numbers. Bookmark data may include the bookmark name, website URL, category, optional remote cover-image URL, and creation date. Backups do not include API keys, imported book files, browsing history, last-read webpage URLs, or detected chapter history.
You can disable automatic backup in Settings. Disabling automatic backup, deleting the app, clearing app data, or deleting data inside YomuLens does not delete backup files stored in the selected folder. You are responsible for deleting backup files through your device or storage provider.
If you select a cloud-synced folder, your device or storage provider may upload and process backup files under that provider’s own privacy policy and terms. YomuLens does not operate a backup server and does not itself upload these local backup files.
Cached files, such as webpage images, reader images, cover images, and pronunciation audio, may also be removed by clearing app data or uninstalling the app, depending on your device and operating system.
To request deletion of personal data that may have been provided directly to us, contact:
Please note that we may not be able to delete data held by third-party services. You may need to contact those providers directly or manage your data through their account settings.
Children’s Privacy
YomuLens is not intended for children under 16 years of age, or under the age of digital consent required by applicable law.
We do not knowingly collect personal information from children. If you believe that a child has provided personal information to us, please contact us at [email protected] and we will take appropriate action.
Security
We take reasonable technical and organizational measures to protect information processed by the Application.
For example, user-provided API keys are stored using secure storage where supported, backup exports do not include API keys, and the app is designed to minimize direct collection of personal information.
However, no method of storage or transmission is completely secure.
Data Breach Notification
Where required by applicable law, we will notify the relevant supervisory authority and affected users of a personal data breach within the required timeframe.
Your GDPR Rights
If you are located in the European Economic Area, the United Kingdom, Switzerland, or another region with similar rights, you may have the right to:
- Access your personal data.
- Correct inaccurate data.
- Request deletion of your data.
- Restrict processing.
- Object to processing.
- Request data portability.
- Withdraw consent where processing is based on consent.
- Lodge a complaint with a data protection authority.
To exercise your rights, contact:
You can find EU data protection authority contact details here:
https://edpb.europa.eu/about-edpb/members_en
If you are in the United Kingdom, you may contact the Information Commissioner’s Office:
California Privacy Rights
If you are a California resident, you may have rights under the CCPA/CPRA, including the right to know, delete, correct, and opt out of certain sharing of personal information.
YomuLens does not sell personal information directly. However, advertising services may involve processing that could be considered “sharing” under California privacy law. Where required, you may be offered controls to manage advertising-related choices.
To exercise applicable rights, contact:
Changes to This Privacy Policy
We may update this Privacy Policy from time to time. If we make material changes, we will update the effective date and, where required by law, request your consent or notify you in the Application.
Contact and Data Controller
YomuLens is operated by Anthony Smadja, a French micro-entrepreneur.
Country: France
Email: [email protected]
Anthony Smadja is the data controller responsible for the processing of personal data described in this Privacy Policy.
For privacy questions or to exercise your data protection rights, please contact us at the email address above.