For learners

Privacy Policy

Bamboo Island is built to work offline and to keep your family's content on your own device. This page explains, in plain language, what the app stores, what can leave the device, and the choices you have.

The short version

What we collect

We do not collect personal data. Specifically:

What is stored on the device

The content you and your family create is saved in a private on-device SQLite database and the app's local storage. This includes:

This data stays on the device. It is never sent to us or to any server we operate. Uninstalling the app removes all of it.

Features that can send data off the device

The app is offline-first, but the following optional features involve another service. Each one is off by default or requires an action from you.

1. AI translation & drafting (optional, off by default)

The app can use AI to translate sentences or draft conversations. This feature is hidden until you configure it. To enable it, you enter an API key for a third-party AI provider of your choice β€” such as Google Gemini, OpenAI, Groq, OpenRouter, or any OpenAI-compatible service.

2. Voice typing and read-aloud recordings (the 🎀 microphone)

The microphone is used in two different ways, and they behave very differently:

3. Text-to-speech voices

The app reads Chinese aloud using your device's text-to-speech engine. On most devices this is fully on-device. If no local Chinese voice is installed, the system may stream a voice over the internet. Only the text being read aloud is involved, and it is processed by the device's speech service β€” not by us.

4. Backup & restore

You can create a backup of all app data as a single file and save it wherever you choose (for example, your Downloads folder or cloud drive). This is something you initiate β€” the app never backs up or uploads data on its own. The backup file contains your stories, conversations, flashcards, and settings, and you decide where it goes and who, if anyone, sees it.

Permissions the app requests

Permission Why it is needed
Microphone For voice typing when you tap the 🎀 button, and for recording yourself reading a story or conversation. Recordings stay on the device. Off until used.
Notifications For the optional daily review reminder, which you can turn on and schedule.
Alarms To deliver the review reminder at the time you chose.
Run at startup To re-arm the reminder after the device restarts.
Vibrate So the reminder can buzz when the daily streak is at risk.
Network access Only for the optional features above (AI, cloud voice typing, and cloud text-to-speech voices). The core app works without any internet connection.

Children's privacy

Bamboo Island is designed for learners of all ages, including families. The app collects no personal data from anyone β€” child or adult. There is no account, no profile, and no way for the app to identify you or your family. The optional AI feature is gated behind adult configuration and never activates on its own. Voice typing uses the device's own speech service and asks for permission before listening.

Because there is no account and no data collection, there is no data about you for us to use, share, or sell. You can remove everything at any time by uninstalling the app.

Your choices

Third-party services

If you choose to use them, the following third parties may process data under their own privacy policies. We are not responsible for their practices:

We do not share data with any third party, because we do not collect any.

Changes to this policy

If the app's data practices change, we will update this page and revise the "last updated" date below. Since the app collects no personal data and has no account system, we have no way to notify you directly β€” please check this page periodically.

Contact

If you have questions about this policy, please contact the developer at bambooisland.app@gmail.com.

Privacy Policy Β· Bamboo Island (语言岛) Β· Last updated: 2026-08-27