Privacy Policy

Sylvarium is designed to keep your data yours. No accounts. No tracking. No advertising. Your vocabulary and books live in your browser — not on our server. The exception is Bibliomuse (community reading lists), where lists and recommendations are stored on our server so other users can see them.

The following is stored locally in your browser using IndexedDB and localStorage, and never transmitted to our server:

• Words you have looked up, along with example sentences, references, and revision history
• Books you have added, including title, author, reading status, and library loan dates
• App preferences such as colour theme and display settings

You can export all this data as a JSON file, import it on another device, or delete it at any time from the Settings page.

Your words and books are stored in plain text in your browser's local storage. They are not encrypted. Someone who has access to your device and knows to look in the browser's developer tools could read your data — in the same way they could open a notes app and read your notes. Your data is not visible to anyone on the internet, or to us. If you share a device with others, be aware that your vocabulary list would be visible to anyone using the same browser profile.

The following types of request are sent externally when you use specific features:

• Word lookups — the word you search for is sent to the Wiktionary API, operated by the Wikimedia Foundation. This also covers pronunciation, etymology, synonyms and antonyms.
• ISBN lookups — when you scan a book barcode or enter an ISBN manually, the ISBN is sent to the Open Library API, operated by the Internet Archive.
• Bibliomuse book pages — when a book is added to a reading list, the title and author are sent to the Wikipedia API in the background to fetch a related link. No personal information is attached beyond the book details you submitted.
• Photos for text extraction or barcode scanning — images you choose are uploaded to our server, processed in memory by local software (Tesseract OCR / pyzbar), and immediately discarded. No image is stored on disk.
• Bibliomuse (community reading lists) — if you create or contribute to reading lists, the following is sent to and stored on our server: your chosen username, the reading list names and book titles you add, and any recommendation text you write. Your username is visible to all users of Bibliomuse. A device token (a randomly generated identifier) is stored on your device and on our server to associate your contributions with your username — this is not linked to your name, email, or any personal account.

We do not control the privacy practices of Wikimedia or the Internet Archive. Please review their privacy policies via the links above.

Our server keeps a rolling 30-day count of API requests made. This is purely aggregate and contains no personal information.

For security purposes, a request log is kept on disk. Each entry records the time, URL path, response code, IP address, and a truncated User-Agent string. Only the most recent 300 requests are retained. This information is used solely to identify and block bots and attackers, is not shared with anyone, and is only accessible to the site administrator.

Bug reports you choose to submit are stored on our server and are only accessible to the administrator. Only the most recent 200 are retained.

Bibliomuse data — reading lists, book entries, recommendations, and usernames are stored in a database on our server for as long as the service operates. If you would like your Bibliomuse contributions removed, contact the developer.

Sylvarium uses no cookies. Browser localStorage is used to remember your preferences (colour theme, display settings). This data never leaves your device.

No third-party analytics, advertising, or tracking scripts are loaded. All fonts are served directly from our server.

All vocabulary, book, and preference data is in your own browser — you are in full control. You can delete everything from Settings → Danger Zone.

For Bibliomuse contributions stored on our server (reading lists, recommendations, username), you can request deletion by emailing the developer.

You are responsible for ensuring that any text you add complies with applicable laws. This app is intended for personal, non-commercial study use. Avoid copying large sections of text.

Questions about this policy? Email the developer.