TarnVPN

🛡️ TarnVPN is an open-source Android VPN client based on sing-box, with a custom networking core derived from sing-box-lx. It provides a clean interface for managing proxy configurations, testing connections, and routing Android traffic through a VPN tunnel.

The project focuses particularly on modern VLESS, REALITY, and XHTTP configurations while retaining the flexibility of the sing-box ecosystem.

🚀 Main Features

• sing-box powered — built on a customized sing-box-lx core with additional networking improvements.

• VLESS & REALITY — support for modern VLESS configurations with REALITY and related TLS options.

• XHTTP support — includes advanced XHTTP transport capabilities and an XHTTP transport pool in the bundled core.

• TLS Fragmentation — supports TLS fragmentation for compatible REALITY configurations.

• Multiple transports — supports connection transports provided by the underlying sing-box core, depending on the imported configuration.

• Subscription support — import a subscription URL or individual proxy links directly from the main screen.

• Server management — organize multiple servers and subscriptions in one place and easily switch between configurations.

• Real connection testing — test a selected server using an actual HTTPS request through the established tunnel instead of relying only on basic latency checks.

• Connection recovery — automatically restart the VPN when network connectivity changes, such as switching between Wi-Fi and mobile data.

• Fallback server — configure an alternative server that can be used when the active connection becomes unavailable.

⚡ Real Tunnel Testing

TarnVPN can perform an actual HTTPS request through an established VPN tunnel to verify whether a selected server is working correctly.

The test can use its own target address, timeout, and retry settings, providing more useful information than simply checking whether a server responds to a basic ping.

🔄 Connection Recovery

Network changes can interrupt VPN connections, especially when moving between Wi-Fi and mobile networks.

TarnVPN can detect these changes and restart the VPN connection when necessary. A fallback server can also be configured for additional recovery options.

📦 Configuration Management

TarnVPN is a client, not a VPN service.

There are no built-in proxy servers or subscriptions. Users provide their own server configurations or subscription links, which TarnVPN then manages and connects through the bundled networking core.

Supported configurations depend on the capabilities of the included sing-box core.

🔐 Privacy

TarnVPN does not require an account or subscription to use the application.

According to the project information, connection traffic is sent to the servers configured by the user. The application does not provide or operate its own proxy infrastructure.

🛠️ Diagnostics

For troubleshooting, TarnVPN provides access to the live core output directly from the application.

Different log levels can be selected depending on how much diagnostic information is required. Detailed logging can contain visited domain information and may increase battery usage, so it is intended primarily for troubleshooting.

🌐 Interface

TarnVPN provides a straightforward Android interface focused on server management, connection control, testing, and diagnostics.

Languages: English 🇺🇲 and Russian 🇷🇺

The interface follows the system language when supported.

📱 Android

TarnVPN is designed specifically for Android and supports common Android device architectures, including ARM64, ARMv7, x86, and x86_64.

The application uses Android's VPN service to provide system-level traffic routing through the selected configuration.

🔓 Open Source

TarnVPN is an open-source project derived from the sing-box-for-Android ecosystem, with its own downstream sing-box-lx modifications.

The project is not affiliated with or endorsed by sing-box, SagerNet, or the original authors of sing-box-lx.