Data & legal

Privacy

Mimora helps you study Japanese from the videos, articles, scenes, recordings and documents you choose. This policy covers the Mimora Android app, browser extension, and their account, synchronization and billing services. We do not sell personal data or use learning content for advertising.

Dictionary lookup, grammar matching and local review run on your device. Your settings, saved words, grammar, example sentences and review history are stored on your device. When you sign in, account-linked learning data and settings are sent to our API and Supabase to synchronize your learning. Saved examples can include source video or article titles, URLs and sentence text. Full extracted article bodies are processed locally and are not uploaded as full articles to our news service.

Information sent to other services

• Supabase handles account authentication and stores synchronized account data. Sign-in is optional. The Android app offers Google, Discord and email sign-in, subject to provider availability. Depending on the sign-in provider, account profile information may include your email address, account identifier, display name and avatar URL.
• If you use a version of Mimora that offers AI-content reporting and choose to submit a report, we collect the selected text shown in the confirmation screen (up to 4,000 characters), your selected reason, a limited content reference and your account identifier to investigate the report and improve safety. Reports are processed through Cloudflare and stored privately in Supabase for developer review. Reporting does not automatically send your full conversation, audio or other original media. Once account deletion completes, reports linked to that account are removed from Mimora’s report queue. Separate provider operational records may follow their own retention policies.
• YouTube supplies video search results and the official embedded player. Opening a video connects your browser to YouTube, which applies its own privacy policy.
• When sentence translation is requested, the text to translate and language selection are sent to Google Translate. Bundled vocabulary definitions and grammar explanations do not require this service.
• When you request cloud AI assistance, your question, relevant sentence or word context, language preferences and a limited recent conversation context are sent through our API to the configured AI provider (currently OpenRouter and its selected model provider). Avoid submitting sensitive personal information in questions. Local chat history remains in your browser.
• Transcripts: watching a third-party video does not upload that video to our storage. When you import your own audio or video file for transcription, Mimora uploads the original file and audio chunks to private cloud storage (Cloudflare R2). Recorded audio is also uploaded when you choose to record. Audio needed for transcription is sent through our API to OpenRouter and its transcription provider to produce Japanese text. Imported document text and resulting transcripts are stored with your account for study and synchronization. Private transcript files are associated with your account, are accessed through our authenticated API, and are not published for other learners. Deleting a transcript removes its stored originals and audio chunks; account deletion removes your private transcripts and their uploaded files. Recording happens only while you are recording and after you allow microphone access.
• Voice: scene lines, news sentences you ask to hear and replies in free conversation are read aloud by a speech service through our API (currently OpenRouter with ElevenLabs). For scenes, the scene's own text is sent and the resulting audio is kept and shared with everyone who studies that scene. For news, the sentence is sent each time and nothing is kept on our servers; the audio is cached on your device. In free conversation, your message and the recent conversation are sent to the configured AI provider to write the reply.
• Purchases inside the Google Play version of Mimora use Google Play billing. Purchases on the Mimora website and supported direct-distribution versions use Stripe. These providers process payment details; Mimora stores billing identifiers, purchase records, plan and payment status rather than your full card number.
• Usage analytics and client diagnostics are on by default, and you can turn them off at any time in settings. PostHog receives selected learning-flow events, video IDs, hashed item identifiers, counts, duration ranges, language, platform, version, plan and a pseudonymous account or installation identifier. Sentry receives filtered error reports and application stack locations. Neither receives subtitle or article text, saved word text, AI conversations, email addresses, request bodies or authorization headers through these reports. Session replay and automatic click tracking are disabled. We do not use this information for personalized advertising or sell it to data brokers. Previously sent data is not automatically deleted when you turn the setting off.
• PostHog may use anonymized, aggregated data derived from analytics for its own AI features under our current organization settings. Turning off Mimora’s optional reporting does not retroactively remove data already processed.
• Our API may send filtered operational failures to Sentry independently of optional client analytics. These reports exclude request bodies, credentials and learning text. Network providers necessarily receive the IP address used to make a request; analytics geolocation enrichment is disabled.
• Cloudflare hosts our API. Operational requests include network metadata such as IP address; application logs record request IDs, route, error status and account ID for diagnosis. We do not intentionally log full article bodies or translation text.

Browser access

Mimora requests access to a publisher's website when you choose to study its content. You can refuse or revoke that access in Chrome's extension settings. Required host access covers the YouTube player integration and Google Translate. We do not collect a general history of unrelated pages you visit. The microphone is used only while you record a transcript, after you allow it; you can revoke that permission at any time in your browser or phone settings.

Your choices and data requests

You can use local learning without signing in. Clearing local data or uninstalling the extension does not delete previously synchronized account data, and local-only data may be lost when browser storage is cleared. Account data is kept for as long as your account exists.

Deleting your account

You can delete your account yourself at any time: in the Android app (⚙ → Settings & account → Delete account), or on the web without installing anything, at mimora.org/account-deletion. Deletion is immediate: your sign-in account, profile, settings, saved words and grammar, learning records and progress, synced data and device list, transcripts, imported document text and uploaded original audio or video files, AI usage records and the billing records Mimora holds are deleted. A subscription bought on our website is canceled and a Google Play subscription is stopped from renewing at that moment, so nothing more is charged; amounts already paid, including a Lifetime pass, are not refunded. Stripe and Google Play keep their own payment records as tax and accounting law requires; analytics and diagnostic events already sent carry only a random or hashed identifier and expire on the providers' schedule. Recovery copies, if maintained, are separately retained for recovery and are not used to reactivate a deleted account.

For other requests, such as access to your data, contact Mimora support through our Discord support community. Ask for a private support conversation; do not post passwords, payment details or learning records in public channels. We may verify account ownership before acting.

Mimora's use of information received from Google APIs adheres to the Chrome Web Store User Data Policy, including its Limited Use requirements. Data is used to provide or improve the user-facing features described here, not for personalized advertising, creditworthiness or sale to data brokers.

Terms of use

Use Mimora only with content you are entitled to access. Do not misuse the service, interfere with its operation, bypass platform protections, or redistribute third-party content.

Paid access follows the plan selected at purchase. Product availability and features may evolve; material billing changes will be communicated before taking effect.

Third-party notices

Dictionary data includes JMdict, provided under CC BY-SA 4.0. JLPT levels shown by Mimora are estimates and are not official rankings or a published JLPT syllabus.

YouTube playback uses the official embedded player. YouTube and other third-party services remain subject to their own terms and privacy policies.