Privacy Policy

Information we collect

Hibi Mondai may collect account and learning information needed to provide the service, including:

• Email address used for account authentication.
• Username and display name.
• Desired JLPT training level.
• Japanese sentences submitted by the user.
• Daily challenge answers and extra practice attempts.
• Streak, progress, and practice history.
• Classroom, teacher review, and feedback data when a user joins a classroom.
• AI教師 (AI feedback) results, when a user chooses to request them, saved as part of their learning history.

How we use information

We use this information to authenticate users, show daily grammar challenges, save answers, track progress, support classroom review, and improve the learning experience.

Authentication and storage

Hibi Mondai uses Supabase for authentication, database storage, and backend access control. User data is stored to support the app features described above.

User-generated content

The sentences users submit are saved so users can review their history and, when applicable, receive teacher feedback. Users should avoid submitting sensitive personal information in practice sentences.

AI教師 (AI feedback)

AI教師 is an optional feature that you choose to use. It is never triggered automatically — AI feedback is only generated when you tap to request it on one of your own submissions.

• When you request AI教師 feedback, the Japanese sentence from that submission, together with the related grammar point and your training level, may be sent to a third-party AI provider, currently OpenAI, to generate the feedback.
• AI教師 feedback is AI-generated and may be imperfect or incorrect. It is intended as a study aid, not as authoritative correction.
• The resulting AI feedback is stored in the app as part of your learning history so you can review it later.
• Please do not include sensitive personal information in the sentences you submit, since they may be processed by the AI provider.

Data sharing

We do not sell personal data. Data may be processed by service providers used to operate the app, such as authentication, database, hosting, email infrastructure, and — when you request AI教師 feedback — an AI provider that generates that feedback.

Classroom visibility

If a user joins a classroom, classroom managers such as teachers or admins may be able to view relevant submissions and provide feedback as part of the learning workflow.

Data deletion

You can delete your account and learning data yourself at any time from delete your account on the web, or in the iOS app under Settings → Danger zone. Deletion happens immediately, is irreversible, and requires being signed in to the account. Some minimal records may be retained where required for legal, security, abuse-prevention, or operational reasons. If you need help, contact support@hibimondai.app.

Changes to this policy

This policy may be updated as Hibi Mondai adds features, expands testing, or prepares for broader public availability.

Contact

Questions about this policy can be sent to support@hibimondai.app. See the Terms of Service for the rules around using the app.

A note on these documents

These are founder-drafted launch documents intended to be clear and practical for an early-beta learning app. They should be reviewed by legal counsel before any broad commercial launch.