Why this exists
A group of friends, the Nitro Poker Club, wanted one simple thing: to talk and see each
other's screens (a game, a YouTube video with sound) without creating accounts, installing
anything heavy, paying for a subscription, or handing their conversations to a company.
Big tools solve this by routing everything through their own servers. NitroCall does the
opposite: the friends' own devices are the infrastructure. The page is a static file. Once
it's open, GitHub is out of the picture: audio and screen go straight from one device to
another.
There is no commercial intent. No paid tier, no ads, no data collection, no "pro version".
The project is, and will stay, free and open.
What it does
- 🎙️ Voice in Opus 64 kbps with loss protection and AI noise suppression (RNNoise).
- 🖥️ Screen sharing up to 1080p30, with your PC's sound (video, games, music), with
automatic quality adjustment when someone's internet can't keep up.
- 📱 Phones: join from the browser, talk, listen, watch screens in fullscreen, and show
your camera (rear or front).
- 🔒 End-to-end encryption (DTLS-SRTP, mandatory in WebRTC), verified automatically:
each side signs the connection's security code with the room key, so a 🔒 next to a name
means nobody is in the middle — no codes to read out loud.
- 🌉 Never without a path. NitroCall tries, in order:
- direct between the two devices;
- a friend in the room as a bridge, picked automatically by connection quality;
- TURN, a relay server, only when there's no direct path and no friend who can bridge.
Media stays encrypted: TURN forwards packets it cannot open.
- 🎲 No sign-up: pick a room code and the app gives you a funny random name
("Pocket Pair Without Wi-Fi", "Joker in Pajamas"…). You can change it.
- 🔗 One-tap invites: tap the room name to copy a link; whoever opens it lands in the room
with everything filled in and just taps "Join".
- 🧭 Four buttons: mic, share, ⋯, leave. Everything else lives in the ⋯ menu or right on
the thing it controls (screen controls sit on your own preview).
- 🌎 Portuguese and English (Portuguese by default; switch anytime).
- 🌐 Nothing to install: it runs in the browser, on desktop and on phones. Open the link
and you're in.
How it works (no jargon)
You open the link ──► GitHub serves the page (~2.4 MB, once)
│
▼
Devices find each other at a public "meeting point" (PeerJS; backup: Nostr)
│
▼
The call goes DIRECT between devices (WebRTC) ← almost always
or through a FRIEND in the room acting as bridge ← when two can't reach each other
or through TURN, still encrypted ← last resort
An hour-long call does not use an hour of our server. GitHub only serves the file; the
call's bandwidth is carried by the participants themselves, like a phone call between two
phones.
Transparency: third parties and what each one sees
"No server" means no media server and no server of ours storing data. To find each other,
NitroCall relies on free public services:
| Service | Used for | What it sees |
|---|
| GitHub Pages | serving the page | that someone opened the site (like any website) |
| PeerJS (0.peerjs.com) | meeting point: reserving your slot in the room | an identifier derived from the room code (hash), IPs |
| Public Nostr relays | backup meeting point if PeerJS is down | signaling messages encrypted with the room key |
| STUN (Google/Cloudflare) | each device learning its own public address | your IP |
| TURN (Cloudflare) + Worker | last-resort relay | IPs and encrypted packets; it cannot hear or see anything |
The room code lives after the # in invite links and is never sent to GitHub.
Where it's been tested
| Device | Browser | How | Result |
|---|
| iPhone (iOS 18.7) | Safari, Chrome, Brave | real device, Wi-Fi and 4G, with bots in the room | joins, hears/is heard, 🔒, camera both ways, relay via TURN |
| Windows | Chrome, Edge | automated suites (200+ checks) and real use | everything |
| Android | Chrome (engine) | automated, emulated phone profiles | joins, camera, background/return |
| iPhone/Android | any | automated "WebKit-like" checks (strict ICE config, Safari adapter, blocked Worker) | joins |
Not verified on real hardware yet: Android phones, iPad, Firefox. If something fails there, open the
link with &debug=<any-word> at the end and send the maintainer that word — the app streams its log
live (encrypted) so the problem can be seen as it happens.
Honest limits
- Designed for 2 to 8 people. 9–10 works but is experimental: whoever shares a screen
sends one copy per viewer (or to friends who redistribute it), and home upload runs out.
- Phones can't share their own screen from a browser. Neither Android nor iPhone allow it
for websites; NitroCall offers the camera instead.
- iPhone in the background: iOS cuts any website's microphone when you switch apps.
NitroCall tells the others ("left the tab") and restarts your mic when you come back.
- TURN depends on a third-party service with a free quota (1,000 GB/month). If it ever
goes away, NitroCall keeps working with direct links and friend bridges.
- Best on desktop Chrome or Edge (they send your PC's sound along with the screen).
Built with Claude: a 100% "vibe coding" project
To be upfront: this project was written together with Claude by
Anthropic, using Claude Code (CLI).
I decided what I wanted, tested it with real friends, complained about what was bad and set
the direction; Claude wrote practically all of the code, the automated tests and the docs, and
helped investigate every problem (NAT, codecs, GPUs, screen quality).
NitroCall is part of my learning roadmap for Anthropic's tools: Claude Code, agents,
AI-driven testing, and how to build something real and useful with them. If you're learning
the same, feel free to read the history, borrow ideas and open issues.
Running or changing it
Source code, tests (multi-browser end-to-end, an image-quality lab and a network emulator)
and build instructions live in app/. The optional TURN credentials Worker is in
app/cloudflare/turn-worker/.
License
MIT. Use it, copy it, change it, share it.
Nitro Poker Club · made among friends, for friends.
