Privacy Policy

This policy covers betterlingo.io and the BetterLingo app. BetterLingo is the data controller for the personal data described here.

1. What we collect

• Account data. Your username, email address, and — if you sign in with Google — the Google account identifier and the email address on that account. If you register with a password we store a hash of it, never the password itself.
• Study data. Your answers, quiz attempts, review history, kanji progress, streaks, bookmarks, chosen JLPT level and native language. This is the substance of the product: without it there is no progress to show you.
• AI conversation data. The Japanese you submit for grading and the messages you send the tutor, together with the responses generated.
• Billing data. Whether you hold a subscription, its status, period dates, and the identifiers Lemon Squeezy gives us for your customer and subscription records. We never receive or store your card number.
• Technical data. Server logs containing IP address, user agent, requested URL and timestamps, kept for security, abuse prevention and debugging.
• Referral data. If you arrive through a referral link or a campaign link, the source that sent you.

2. Analytics

We use a self-hosted installation of Plausible Analytics. It is cookieless, does not track you across sites, does not build a profile of you, and reports only aggregate figures such as page views and referrers. We do not use Google Analytics, advertising pixels or cross-site trackers.

3. Cookies

We set a session cookie so you can stay logged in, and a security cookie to protect forms against cross-site request forgery. Both are strictly necessary to operate the service; we set no advertising or profiling cookies.

4. Why we are allowed to process it

Where UK/EU data protection law applies, our legal bases are: performance of a contract (running your account, delivering study features, handling your subscription); legitimate interests (keeping the service secure, preventing abuse, understanding aggregate usage); and legal obligation (tax and accounting records held by our merchant of record).

5. Who else processes your data

We use a small number of processors, each for one job:

• Railway — application hosting and the PostgreSQL database.
• Cloudflare — DNS and edge protection for the site.
• Lemon Squeezy — payments, invoicing and tax, as merchant of record.
• Resend — transactional email (verification, password reset, account notices).
• OpenRouter and the model providers it routes to — AI grading, hints and tutoring. The Japanese you submit for grading is sent to them to produce a response.
• Google — only if you choose to sign in with Google.
• Plausible — analytics, self-hosted by us on our own infrastructure.

We do not sell your personal data, and we do not share it with advertisers.

6. International transfers

We operate from Japan and our processors operate in the United States, the European Union and elsewhere, so your data will be transferred outside your country of residence. Where UK/EU law applies, those transfers rely on the standard contractual clauses or an equivalent safeguard in our processors' terms.

7. How long we keep it

Account and study data is kept for as long as your account exists. If you ask us to delete your account we remove your personal data within 30 days, except where we must keep records for a legal reason — most commonly the order and tax records held by our merchant of record. Server logs are kept for a short operational period and then discarded. Analytics data is aggregate and holds no identifier for you.

8. Your rights

Depending on where you live you may have the right to access a copy of your data, to correct it, to delete it, to restrict or object to processing, to take it elsewhere in a portable form, and to withdraw consent. Write to [email protected] and we will respond within 30 days. If you believe we have handled your data wrongly, you may complain to your local data protection authority.

9. Children

The service is not directed at children under 13, and we do not knowingly collect their personal data. If you believe a child has given us data, write to [email protected] and we will delete it.

10. Security

Traffic is encrypted in transit. Passwords are stored only as hashes. Access to the production database is restricted. No system is perfectly secure. Where a breach affects your personal data, we notify you and the relevant authority as the law requires.

11. Changes

We may update this policy. The date at the top shows when it last changed, and we will tell account holders about a material change before it takes effect.

12. Contact

Privacy questions and data requests: [email protected].