KMH-JP Privacy Policy

KMH-JP ("KMH-JP," "we," "us," or "our") is an educational Japanese-language learning service available on the web and as an Android app. It is used with school or institutional management: student access is provided through administrator-created accounts rather than open self-registration.

This Privacy Policy explains what information the service processes, what is stored, and how we handle microphone, speech, and audio features. By using KMH-JP, you agree to the practices described here. If you do not agree, please do not use the service.

Students cannot self-register. Student accounts are created and managed by administrators on behalf of a school, program, or institution.

Account-related information may include:

• Email address and password (managed through Supabase Auth)
• Username and display name
• Full name provided when the account is created
• Role, account status, JLPT level, and activity flags stored in your profile

When you sign in, we maintain authentication session cookies and, for students, a secure student session cookie plus a single active session record that includes a device identifier and last seen timestamp. This enforces one active student session at a time.

When you use learning features while signed in, KMH-JP stores progress and activity in our database through Supabase. Depending on the feature used, this may include:

• Lesson progress, completion status, study minutes, and last accessed timestamps
• Vocabulary and grammar learning or bookmark records
• Course enrollment records
• Quiz attempt scores, pass/fail results, and individual quiz answers

Some practice features operate only in your current browser or app session and are not saved to our database. For example, pronunciation practice scoring, simulated test sessions, and reading or listening practice sessions are handled in the app during use unless you choose to export a result locally (such as a PDF).

KMH-JP requests microphone access only when you use features that require speech input or live audio, such as pronunciation practice or conversation practice.

We do not permanently store your microphone recordings. The app uses the microphone to capture speech in real time for recognition or live conversation. Audio is not uploaded to KMH-JP servers as a saved recording file.

On Android, microphone permission is requested through the device operating system when needed for speech recognition.

KMH-JP uses speech recognition to convert spoken Japanese into text for learning features such as pronunciation practice and live conversation captions. Depending on your platform:

• In supported web browsers, the app may use the browser's built-in speech recognition service.
• In the Android app, pronunciation practice uses native device speech recognition through a Capacitor plugin after microphone permission is granted.

Recognized text is used during your session—for example, to score pronunciation or display live conversation captions. KMH-JP does not store pronunciation recognition results or conversation transcript text in our database as permanent account records.

Speech recognition may be processed by your browser, mobile operating system, or device platform provider. Their handling of audio and transcripts is governed by their own policies, not this policy alone.

KMH-JP uses audio in several ways:

• Playback: You can play lesson audio, example sentences, listening exercises, and other learning content streamed from our content storage.
• Generated speech: When no human-recorded audio is available, the app may generate Japanese speech audio using Google Cloud Text-to-Speech based on lesson text you request to hear.
• Live conversation: During conversation practice between signed-in users, live audio may be transmitted directly between participants using WebRTC. Call setup uses Supabase Realtime for ephemeral signaling and public STUN servers for connection discovery. KMH-JP does not record or store those live audio streams on our servers.
• Conversation transcripts: Text transcripts generated during a conversation session are kept in memory for display during the session and shared ephemerally with your conversation partner. They are not saved to our database.

Administrator-uploaded lesson audio and images are stored in Supabase Storage as learning content. These files are not recordings of student speech.

Generated text-to-speech audio files may be cached in Supabase Storage so repeated playback of the same lesson text does not require regenerating audio each time. These cached files are based on lesson text and voice settings, not on a recording of your voice.

KMH-JP uses Supabase for authentication, database storage, file storage, and realtime messaging features. Information stored or processed through Supabase may include:

• Account and profile data
• Learning progress and quiz results
• Uploaded learning content such as images and audio files managed by administrators
• Cached generated audio files
• Ephemeral presence and signaling data for conversation practice

Supabase processes this information as our infrastructure provider. Their security and privacy practices apply to data hosted on their platform.

When the app generates spoken audio from Japanese text, the text and voice settings are sent to Google Cloud Text-to-Speech on our server. Google returns synthesized audio, which may then be cached in Supabase Storage for reuse.

We do not send your voice recordings to Google Cloud Text-to-Speech. Only text content needed to produce lesson or exercise audio is transmitted for synthesis.

KMH-JP uses cookies and local storage for essential app functionality, including:

• Authentication session cookies managed through Supabase
• A secure student session cookie used for active session management
• Local storage preferences such as theme and certain study display settings

We do not use third-party advertising or analytics trackers in the current version of the app.

We use industry-standard safeguards appropriate to a web application, including HTTPS, authenticated access to protected areas, server-side access controls, and secure cookie settings in production.

No method of transmission or storage is completely secure. While we work to protect your information, we cannot guarantee absolute security.

Account, profile, and learning progress data is retained while your account remains active and as needed to operate the educational service. Cached generated audio and administrator-uploaded learning content may remain stored until replaced or removed as part of content management.

Session-only data such as pronunciation attempt text, simulated test results, and conversation transcripts in memory are not kept as permanent account records.

To request access, correction, or deletion of account-related information, contact us at kyawminhtun7699@gmail.com. Because student accounts are administrator-managed, deletion or correction requests are currently handled through administrator or support review.

KMH-JP is an educational service intended for use with administrator-managed student accounts under school or institutional oversight. It is not designed for independent open sign-up by young children.

Parents, guardians, schools, or institutions responsible for student access should contact us at kyawminhtun7699@gmail.com if they have questions about a student account or believe an account should be corrected or removed.

We may update this Privacy Policy from time to time. When we do, we will revise the effective date at the top of this page. Material changes may also be communicated through the app or by other reasonable means.

Your continued use of KMH-JP after an updated policy becomes effective means you accept the revised policy.

For privacy questions, account support, or data access, correction, or deletion requests, contact:

kyawminhtun7699@gmail.com