A real Linux, unrooted
A SHA-256-verified proot runtime installs Ubuntu 24.04.1 LTS on demand. You get a genuine bash, real apt and a real toolchain, driven by a hand-written POSIX PTY in C and a pure-Kotlin VT emulator.
v1.0.0 is out
An AI coding agent
An AI coding agent
that lives on your phone.
Kern is a real Linux terminal and an AI agent in one app. Give it a folder and an OpenAI-compatible endpoint, and it will read your code, edit it, run your commands and show you the result. No cloud workspace, no SSH tunnel, no root, no desktop.
Rootless Ubuntu
29 agent tools
Keys in the Keystore
Works offline
$ kern agent "explore this project"
29
Agent tools
466
Unit tests
22
Gradle modules
Capabilities
Everything a mobile dev environment needs, and nothing it does not.
Kern is built around one idea: the model should be able to do the work, not just describe it. Every feature below exists to make that possible on a phone.
Twenty-nine agent tools
Files, edits, builds, tests, Git, shell commands, dev servers, previews, plans and memory. Read-only calls run in parallel, mutating ones run in sequence behind your approval.
Nothing destructive runs silently
Every command is classified before it runs. rm -rf, mkfs and git reset --hard always ask, every time. Permission modes decide the rest, and secrets are redacted from every log.
Live preview of what it built
Start a dev server from the agent and a WebView preview opens with a browser-style console drawer. The agent reads that console, runs JavaScript in the page and captures screenshots.
Your keys never leave the device
API keys are encrypted with AES-256-GCM through the Android Keystore. Point Kern at a local model and nothing leaves your network at all.
Works with any OpenAI-compatible model
OpenAI, OpenRouter, Together, Groq, vLLM, Ollama, llama.cpp or your own gateway. Bring your own key and pick the model the agent uses.
A file explorer and editor
Browse the workspace, search across it and edit files with a line-numbered editor, all against the same tree the terminal uses.
A real package manager
Search the full apt index, install and remove packages inside the guest, and watch the output stream in a dedicated log screen.
Built to be looked at
Eleven colour palettes, light and dark, Material 3 dynamic colour and seven terminal themes including a 24-bit truecolour palette.
The interface
Pick a screen and see how it works.
Watch it work
The agent asks before it acts.
A full 93-second capture of a real run: the agent explores a project, requests permission to run a command, reviews its own plan, and finishes at a live root prompt.
- Read-only tools run together, so the exploration is fast.
- Every command that changes something waits for you.
- The plan is shown before it is executed, and can be rejected.
Comparison
How Kern compares to Termux
They solve different problems, and they work well together. Kern can point at a Termux installation.
| Capability | Kern | Termux |
|---|---|---|
| Shell on Android | Built in, with a native PTY and a VT emulator | Built in, long-established |
| Full Linux userspace | Ubuntu 24.04 via proot, installed on demand | Its own package selection |
| AI agent that edits and runs | 29 tools, approval gated | Not included |
| File explorer and editor | Included, sharing the terminal tree | Bring your own |
| Live web preview | Included, with a console drawer | Not included |
| Package management UI | apt, with a browsable index | pkg, from the command line |
Use cases
What people actually do with it.
Learn Linux properly
A real shell, a real package manager, and an agent that can actually run what it explains to you.
Review code anywhere
Open a project folder, ask for a summary, then fix the thing that bothers you before you get home.
Test your web app on the move
Start the dev server, open the preview, read the console. No laptop in the loop.
Run scripts and automation
A quick Python script, a build you kicked off, a cron-style job that keeps running in the background.
Work without leaving a trace
Point Kern at a model on your own machine and nothing, not even a prompt, leaves your network.
Emergency shell access
A working bash on a device with no monitor, no keyboard and no root.
Questions
The things people ask first.
Yes. Kern is free and open source, and its own source is MIT licensed. The only optional cost is whatever your AI provider charges.
No. It uses proot, a userspace chroot and syscall emulator, so a complete Linux environment runs on an ordinary unrooted phone.
Android 9, API 28, and newer. It runs on arm64-v8a, armeabi-v7a, x86 and x86_64 devices. The 32-bit builds get the terminal but not the Ubuntu environment.
Any OpenAI-compatible endpoint: OpenAI and ChatGPT, OpenRouter, Together, Groq, vLLM, Ollama, llama.cpp, LM Studio or your own gateway. The model list comes from the provider, and you pick the one the agent uses.
Yes, and that is the point. You supply the key, it is encrypted on your device with the Android Keystore, and you can point it at a local model if you would rather not send anything to a cloud.
No. Your files stay on the device. Only the prompts and tool results the agent needs travel to the provider you configured, and if that provider is local, nothing leaves your network.
About 65 MB to download and roughly 375 MB once installed. The built-in Android shell works even if you never install it.
Kern is the phone-sized equivalent for quick edits, reviews and small scripts, not a desktop IDE replacement. Because both work on the same folder, you can build on a laptop and review or test from the phone.
Not at the moment. Kern is Android-first, and the phone is the point. The agent, the tool set and the terminal are all portable to a desktop client if that ever changes.
Get started
Put a full dev environment in your pocket.
Download the APK, pick a folder, add a provider, and ask for something. Five minutes to the first agent run.