Zhuzha — Privacy Policy
Last updated: 9 October 2026
Zhuzha is a reading app that compiles study books on your device. It has no server, no account, and no analytics. This policy describes what happens to your data, which is mostly: it stays on your device.
What the developer collects
Nothing. Zhuzha has no backend. The developer operates no server, receives no telemetry, runs no analytics or crash reporting SDK, and serves no advertising. There is no account to create and no way for the developer to identify you or see your books.
Your API key
Zhuzha requires you to supply your own Google Gemini API key. It is stored encrypted on your device, in the Android Keystore via EncryptedSharedPreferences. It is never written to a plain file, never included in a backup made by the app, and never transmitted anywhere except to Google's own API when generating a book.
What is sent off the device, and to whom
To generate a book, Zhuzha sends text to Google's Gemini API using your API key. The app communicates with no other network service of any kind.
What is sent:
- The topic, daily reading time and prior-knowledge description you type when creating a course
- The course outline and previously generated chapters, as context for writing the next chapter
- A passage you select together with the question you ask about it
- A record of how a chapter was read — which passages were asked about or marked, and notes you wrote — used to shape later chapters
- Briefs describing pictures to draw
Because you use your own API key, this traffic is between you and Google under your agreement with Google. Google's handling of it is governed by the Google APIs Terms of Service and the Gemini API terms, not by this policy. Review them if that matters to you: ai.google.dev/gemini-api/terms
Nothing is sent to the developer at any point.
What stays on your device
Your books, chapters, pictures, notes, handwriting, questions, bookmarks and reading progress are written as ordinary files in the app's private storage. They are deliberately plain and inspectable — Markdown and JSON — so they remain readable even if this app stops existing.
Backups you choose to make
If you use the backup feature, Zhuzha writes copies of your books to a folder you pick, using Android's document picker. That folder is yours; the app only writes to the location you grant it. It never uploads anything.
Export
Exporting a book writes an EPUB file to a location you choose. Whether that file leaves your device is entirely your decision. Annotations are excluded from an export unless you explicitly switch them on.
Permissions
Zhuzha requests three permissions, and only the first is used by the app's own code:
INTERNET— to reach the Gemini API. This is the only network use, and the Gemini API is the only host contacted.ACCESS_NETWORK_STATEandWAKE_LOCK— merged in by the Onyx stylus SDK that provides low-latency handwriting on Boox devices. Zhuzha's own code calls neither.
It requests no access to contacts, location, camera, microphone, phone state, storage, Bluetooth, or your photo library.
Children
Zhuzha is not directed at children and the developer does not knowingly collect data from anyone. Books are generated by a third-party AI model from prompts you write; as with any generative model, output is not guaranteed suitable for children.
Deleting your data
Deleting a book from the Library removes its files. Uninstalling the app removes all of its data from your device, including the stored API key. Backups you made to your own folder are not touched — delete those yourself.
Changes
If this policy changes, the date above changes with it.