Privacy Policy

• Account information. Your email address and sign-in credentials, handled through our authentication provider. If you sign in with Apple or Google, we receive the basic account identifier they share with us.
• Learning data. Your study progress, flashcard review history, saved items, and app preferences, so your progress is there when you come back.
• Payment data. If you subscribe, our payment processor handles your card details and tells us only your subscription status. We never receive or store your full card number.
• Diagnostic data. When something goes wrong, we collect error and crash reports to help us fix it. We configure our error monitoring to avoid attaching personal details such as your email to these reports.
• Search data. When a search returns no curriculum result, we store the search terms you entered, the detected writing system, whether dictionary data was shown, and whether JLS has related or subscriber-only content, so we can identify gaps in JLS content and search.

We do not run third-party advertising, we do not use ad-tracking cookies, and we do not sell or share your personal information.

We use the information above to:

• provide the app, your account, and your saved progress (to perform our agreement with you);
• process subscriptions and send service emails such as receipts;
• keep the service reliable, secure, and free of abuse, and diagnose problems (our legitimate interest in running a working service);
• respond to support requests; and
• comply with the law and enforce our Terms of Service.

We share data only with the providers that help us operate JLS, and only so they can perform services for us under contract:

• Supabase (database, authentication, and storage), which holds your account and learning data with row-level security so only you can read your own records.
• Vercel (web application hosting).
• Sentry (error and crash monitoring).
• Stripe (subscription payments).
• Resend (sending account and transactional email).
• Apple and Google (account sign-in).
• Cloudflare (domain and network routing).

Audio in the app is generated with self-hosted software and does not involve sharing your personal data.

JLS is operated from Japan. Your data is stored and processed on infrastructure run by the providers above, which is located in Australia (our database and storage) and the United States (hosting, error monitoring, payments, and email). This means your information may be transferred outside your own country, and outside Japan. Where required, these transfers are covered by the providers’ data processing agreements and standard contractual clauses.

We keep your account and learning data for as long as your account is active. You can delete your account at any time from Settings. Deleting your account removes your data from our database; routine backups and diagnostic logs are retained only for a short period and then expire. We may keep limited billing records where the law requires it.

We protect your data with encryption in transit and database-level access controls, and we limit who can access it. No online service can promise perfect security, but we take reasonable measures to safeguard your information.

Depending on where you live, you may have the right to access, correct, delete, or export your personal data, to object to or restrict certain processing, and to withdraw consent. You can update or delete most of your data directly in Settings, or email us at support@jls.studio and we will respond. We will not discriminate against you for exercising these rights, and we do not sell or share your personal information.

JLS uses only the cookies and on-device storage needed to sign you in, keep your session, and run the app securely. We do not use advertising or cross-site tracking cookies, so there is no consent banner to dismiss.

JLS is not directed to children, and you must be at least 16 to use it. We do not knowingly collect personal information from children under that age. If you believe a child has created an account, please contact us so we can remove it.

We may update this policy as the service evolves. When we make material changes, we will update the effective date above and, where appropriate, notify you in the app.

For any question about this policy or your data, email support@jls.studio. If you are in Japan, you may also contact the Personal Information Protection Commission; if you are elsewhere, you may have the right to complain to your local data protection authority.