Privacy Policy

Last updated: March 2026

1. Core Principle: Zero Data Collection

Send to X4 is built entirely around the principle of privacy and local-first computing. We do not collect, transmit, or store any of your personal data, reading habits, or device information.

2. How the App Works

When you use Send to X4 (either the browser extension or the mobile applications), all processing of the articles you wish to send happens locally on your own device. The software extracts the text and images locally, generates the EPUB file locally, and sends that file directly to your Xteink X4 e-reader over your local Wi-Fi network.

3. No Cloud Services

Send to X4 does not use any central servers, cloud syncing, or intermediate hosting. Your articles never leave your personal network.

4. Third-Party Analytics

We do not bundle any third-party analytics, crash reporting, or telemetry tools in our software. We don't know who you are, how often you use the app, or what you read.

5. Open Source

To verify these claims, you are welcome to inspect the source code for both the browser extension and the mobile applications, which are freely available on GitHub under the MIT License.