Privacy Policy

HonScan is built around privacy. Never sending anything related to the contents of your books to an external server is the single most important principle of this app.

1. How book content is handled

• Captured and imported images, exported PDFs and OCR-recognised text are all processed inside your browser, on your device.
• They are stored only in your browser's local storage area (IndexedDB). They are never transmitted to or stored on any server, including ours.
• OCR and image processing run in the browser, not through an external API. No part of the book text is sent away for recognition.
• Because the data lives only on your device, it can be lost if you clear your browser data, reset the device, or the device fails. Export important books to PDF and keep your own backups.

2. What our analytics collect

We use Google Analytics 4 to understand usage and improve the app. It is the only analytics tool we use. Collection is limited to the following.

• Information about page views — the URL viewed, referrer, approximate region, device or browser type, and the basic usage signals Google Analytics measures automatically, such as scrolling and time on page.
• Event names and counts only, for these actions:
  • Starting a capture (auto-capture, or choosing a photo)
  • PDF export, searchable PDF (OCR) export, text export
  • The "add to home screen" prompt being shown, and the add being carried out

Nothing related to the contents of your books is included. Images, PDFs, OCR text, book titles and page counts are never sent to any analytics service. Only the event names above are transmitted, with no accompanying parameters of any kind.

3. Cookies and localStorage

• localStorage — stores your display language (Japanese / English), how long to wait before showing the "add to home screen" prompt again, and a visit counter.
• IndexedDB — stores your bookshelf and page images on your device.
• Cookies — the app itself sets no cookies of its own. Google Analytics may set cookies for aggregate usage measurement.

You can clear all of this from your browser settings at any time. Doing so also erases your language setting and everything saved in your bookshelf.

4. Sharing with third parties

We do not provide or sell the information we collect to any third party other than Google Analytics 4, named above. As for book content, we never receive it in the first place, so there is nothing to share.

5. Disclaimer

• The app is provided as is. We are not liable for any damage arising from its use.
• We have no way to recover data lost from your device. Please keep your own backups.
• OCR results may contain errors. Always check the recognised text yourself.
• HonScan is intended for private, personal use. Complying with copyright law and other applicable regulations is the user's responsibility. This page is not legal advice.

6. Changes to this policy

If this policy changes, we will update this page. Significant changes will also be announced in the app.

Last updated: 5 August 2026