Android · one extension · version 2.2.1

A desk phone that brings its own tunnel.

SIPDesk registers one SIP extension and carries the call through a Tailscale userspace tunnel. The phone system stays on its office address. No separate VPN app.

New in 2.2.1: The first time you sign in, type your mobile number on the login screen. The code is texted to it, and once you sign in that number is linked to your extension. If you change phones, ask the office to reset it.

Download SIPDesk.apk 76 MB · arm64-v8a and armeabi-v7a · release build

Install

Upgrading from 1.0.x? Uninstall it first: 2.x is signed with a new release key.
Download the APK on the phone, or copy it over USB.
Open it and allow installation from that source if Android asks.
Allow the microphone, notifications, and full-screen alerts.
Allow the VPN prompt. The phone will not register until the tunnel has a 100.x address.
In Settings tap Scan QR code (or Paste setup link) with the code from your administrator, then tap Save & Connect.

First launch

Headscale server	The URL of your Headscale server. It is not built into the app.
Auth key	A pre-auth key from that server. Later launches reuse the saved node.
Server	The phone system’s office address, such as 192.168.2.104.
Extension	The SIP extension and its password.

A computer already on the tailnet at the office must share the office LAN into the tailnet. The phone system does not run Tailscale and does not get its own 100.x address.