Dev-server preview
Termivoa opens the web page of a dev server that a session runs, full screen in the app on your phone.
Turn on previews
Section titled “Turn on previews”Previews are optional and need a second, private Tailscale address on port 8443. pterm setup asks about it: answer y if the command is correct. With several computers, each computer asks its own question. To set it up later, run:
tailscale serve --bg --https=8443 http://127.0.0.1:8789pterm doctor checks the preview setup.
Open a preview
Section titled “Open a preview”- Start a dev server in a session, such as
npm run dev, or ask Claude Code to start it. - Within a few seconds, the live terminal shows a Preview ready chip with the port, such as
:5173. - Tap Open ↗.
Live reload works. A stopped server shows “Dev server stopped”.
| Control | What it does |
|---|---|
| ‹ terminal | Goes back to the live terminal. |
| ↻ | Loads the preview again. |
| Tell agent | Goes back with the compose sheet open. |
Can I preview a session on another computer?
Section titled “Can I preview a session on another computer?”Yes. With several computers, open a session on that computer, wait for Preview ready, and tap Open ↗. The bar over the page shows the computer’s name and untrusted page, such as vps · untrusted page.
| You need | Why |
|---|---|
A yes to the preview question in pterm setup on that computer |
Each computer shares its own dev servers. Home’s answer does not count for the others. |
| The same new Termivoa on every computer | A session on a computer with an older Termivoa shows no Preview ready chip. |
| Port 8443 of that computer open to your phone in your tailnet | If your Tailscale access rules (ACLs) block it, the preview cannot open. |
| You see | Meaning |
|---|---|
| “Opening preview…” | The app asks that computer’s preview address first. It waits at most 5 seconds. |
| “Can’t open the preview on vps. …” | Nothing answered. See Troubleshooting. |
| vps · pair again, vps · can’t reach or Update Termivoa on vps | That computer does not accept or answer the phone now. The open preview is removed and this text shows. See What if a computer cannot be reached? |
If you added the computer after you opened the app, the app reloads itself once when you first open a preview on it, then shows the preview. You do nothing.
A link alone never opens a preview from another computer. If you open such an address from a message or a web page, Termivoa shows that session’s terminal. Tap Open ↗ there. A reload of a preview that you opened keeps the preview.
What does “untrusted page” mean?
Section titled “What does “untrusted page” mean?”It means that the other computer chooses the page in the frame, not the app. The app shows the computer’s name and untrusted page over every preview from another computer. The page cannot cover or change that bar.
| The page from another computer | |
|---|---|
| Cannot | Read the app, the terminal, your sessions or the app’s sign-in. |
| Can | Show false content, for example a false “pair again” screen. |
Do not type pairing links or passwords into a preview. The real app never asks for them inside a preview. More in Security.
What does ↻ do?
Section titled “What does ↻ do?”↻ loads the preview again from the start. Use it when the page is stuck, or when the frame shows a short refusal text such as “Origin not allowed.”
What are the limits in Safari?
Section titled “What are the limits in Safari?”These limits apply on iPhone and iPad, to previews from home and from other computers.
| When | What happens | Do this |
|---|---|---|
| You go to another page and use the browser’s Back to return to the app | The preview loads again by itself. | If a short refusal text shows in the frame, tap ↻. |
| The previewed page uses its own “back” (for example a back button of the site) | It can move the whole app back, not only the preview. | Open the preview again with Open ↗. |
How are previews kept private?
Section titled “How are previews kept private?”- Only ports that the session’s own programs listen on are shown. Other servers, such as databases, are never offered, even if you type their port.
- The preview runs on a separate address, so the dev site cannot read the app, the terminal or your sessions.
- Every request checks that the phone is still paired, so a removed phone loses the preview within 5 seconds.
- The dev server never gets Termivoa’s cookies or your Tailscale identity.
- The preview is private to your Tailscale devices. Termivoa never uses Tailscale Funnel.
- A preview from another computer is marked untrusted page, and only computers you added and confirmed can be shown.