Turn a used Android phone into a Linux server, no root required.

An old phone is a small, quiet, low-power computer with a battery backup and Wi-Fi built in. ServerBox puts a real Linux distribution on it and keeps an SSH server running, so you can use it like any other box on your network: host services, run scripts and cron jobs, or tinker.

ServerBox is a fork of UserLAnd by CypherpunkArmory (UserLAnd Technologies, LLC) and, like UserLAnd, is licensed under the GPLv3.

• Linux distributions without root. Alpine, Arch, Debian, Kali and Ubuntu run in user space through PRoot. Each one is a headless server image with an SSH server, an editor and the usual tools. Install and uninstall ServerBox like any other app.
• SSH out of the box. Every session runs an SSH server on port 2022. The Sessions tab shows how to connect (ssh -p 2022 <user>@<phone's IP>), the user and the password. Turn on Settings → Allow SSH from the network to reach it from other devices, and add your public keys (optionally with Keys only).
• Stays up. Servers keep running with the screen off and after the app is closed: ServerBox holds a wake lock and a Wi-Fi lock, restarts a server that dies unexpectedly, and can restart your sessions after a reboot (Start on boot).
• Your services start with it. Executables in /etc/serverbox/autostart.d inside the distribution run each time its server starts (logs in /var/log/serverbox-autostart.log), which is the place for databases, web servers and other daemons in guests without a working init.
• Phone storage. Shared storage is available at /sdcard inside the distribution; ServerBox asks for access to a folder the first time a program uses it.
• Coding agents, ready to go. The Claude and Codex apps are Debian with Anthropic's Claude Code or OpenAI's Codex CLI preinstalled, along with Node.js, git and ripgrep. SSH in and run claude or codex; you sign in with your own account or API key. 64-bit phones only.
• Virtual machines where supported. On phones with the Android Virtualization Framework, distributions can also run in a real VM through a companion app.

Apps	New filesystem	Server settings

Get the APK from Releases. ServerBox needs Android 8.0 or later. Every distribution is available for 64-bit ARM (nearly all current phones) and x86_64; 32-bit support varies by distribution.

Releases are signed with this certificate (SHA-256), which you can check with apksigner verify --print-certs serverbox-<version>.apk:

55:40:C1:F2:4F:5D:44:86:C5:96:EF:76:0A:8C:E9:8C:8E:68:FE:45:AF:C9:E9:54:1C:C6:3D:EF:3E:7A:76:B5

Builds from before 1.0 were signed with a different key, so Android can't update them to a release: uninstall the old build first. Uninstalling deletes its distributions and sessions.

1. Install ServerBox and open it.
2. Pick a distribution on the Apps tab. ServerBox downloads it (the setup log shows each step) and opens a terminal.
3. Open the Sessions tab for the SSH command, user and password.
4. To connect from your computer, turn on Settings → Allow SSH from the network, then run the command shown on the Sessions tab.

Android pauses background apps to save battery, which makes a server stop answering once the screen is off. When ServerBox first runs a server it asks to be exempted from battery optimization; allow it. Some vendors add their own restrictions on top:

• Xiaomi / HyperOS / MIUI: in ServerBox's app settings, set Battery saver to No restrictions and turn on Autostart. The default "smart" restriction cuts off background networking.
• Android 12 and later: the phantom process killer can stop long-running processes. ServerBox offers to turn it off through Wireless debugging (Settings → Stop Android killing session processes).

Keep the phone on a charger, and consider reserving its IP address in your router so the SSH address stays the same.

Builds need JDK 17.

./gradlew :app:assembleServerBoxDebug
./gradlew testServerBoxDebugUnitTest :terminal:testDebugUnitTest lintServerBoxDebug

Instrumented tests (Room migrations and DAOs, the terminal's PTY) run on a connected device or emulator:

./gradlew :library:connectedServerBoxDebugAndroidTest :terminal:connectedDebugAndroidTest

./gradlew :app:assembleServerBoxRelease signs the release APK when a keystore is configured in local.properties (or the same names as environment variables); without one it builds unsigned:

KEYSTORE_PATH=/path/to/keystore
KEYSTORE_PASSWORD=...
KEY_ALIAS=...
KEY_PASSWORD=...

The distribution images are built in madeye/ServerBox-Images and published to ghcr.io/madeye/serverbox-<distro>.

ServerBox is forked from UserLAnd and its library (UserLAndLibrary) by CypherpunkArmory (UserLAnd Technologies, LLC), who hold the copyright on the original code. ServerBox's changes are copyright Max Lv. Like UserLAnd, ServerBox is released under the GNU General Public License v3; the full text is in LICENSE and the copyright notices are in COPYRIGHT.