Get your first program running in five steps

1. Add an API key

Settings at the bottom → pick a provider (DeepSeek / OpenAI / Claude / Gemini...) → paste your API key. You can run programs from the Shell page without a key, but chat will not work.

The key stays on your phone (api_keys.json) and is never uploaded anywhere.

2. Pick a model

Settings → Model: each row shows "provider + model name". To save money, select a small model as well — context compaction and summarization get handed to it.

3. Say what you want, in one sentence

Type straight into the Chat page, for example:

• "Write a hello.c in the workspace that prints a multiplication table"
• "Slow down the falling blocks in examples/c/app/tetris.c"
• "Show me how examples/python/app/tetris.py handles key presses"

When each turn ends, time / tokens / cost appear under the bubble.

4. Run it

Files page → tap a file → choose Run. Compiling C on a phone takes a minute or two — do not assume it has frozen.

Or type this into the Shell page:

vml run examples/c/app/tetris.c

5. Edit code

On the Files page, tap a file → tap ✎ in the top right to leave read-only mode → edit → Save. Then tap ▶ in the toolbar to compile and run in place; errors are drawn on the offending cell.

Where to go next