Privacy Policy

Last updated: September 25, 2026

HanziWeave (“the app”) is made by Peter Van Pham (“I”, “we”). This policy explains what data the app uses. Questions: hanziweave@gmail.com.

Your books and reading stay on your phone

The epub books you add, your reading positions, the words you are learning and your reading statistics are stored only on your device. There are no servers and no accounts; we never receive your books or reading data.
Translation happens on your device (Google ML Kit). Your book text is not sent anywhere.
Speech uses your phone’s own text-to-speech engine.
If you use Android’s backup to your Google account, your word progress, settings and reading positions are included in that backup (your books are not). That backup is handled by Google under your Google account settings; we can’t see it.

Ads (free version)

The free version shows ads from Google AdMob. To show and measure ads and prevent fraud, Google’s ads software collects:

your device’s advertising ID and app set ID,
your IP address (which can indicate approximate location),
interactions with ads and basic diagnostic information about the ads software.

This data is collected and processed by Google and, where you allow it, Google’s ad partners (listed in the consent message), not by us. It is sent encrypted. Where the law requires it (for example in the EU, UK and Switzerland), the app asks for your consent before any ads are requested; you can change your choice any time in Settings → Ads → Ad privacy choices. You can reset or delete your advertising ID in your phone’s settings. Learn more: How Google uses information from apps that use its services.

Buying Remove ads turns ads off completely.

Purchases

The one-time “Remove ads” purchase is handled entirely by Google Play. We don’t receive your payment details; the app only checks with Google Play whether you own the purchase.

Usage statistics from Google libraries

Google ML Kit (on-device translation) sends Google anonymous usage and performance statistics (for example which languages were used, device model, errors). It does not send your book text. The translation model is downloaded once from Google.

Deleting your data

Because your data is only on your phone, you control it: remove a book from your library in the app (Books → ⋮ → Remove from library), or uninstall HanziWeave to delete everything it stored. To remove the copy in your Google account backup, delete it under Google → Backup in your phone’s settings. Nothing is kept by us, so there is nothing for us to delete.

Children

HanziWeave is not directed at children under 13, and we do not knowingly collect their data.

Changes

If this policy changes, the new version will be posted on this page with a new date.