Documentation

Last updated: 2026-06-11

Even Hub apps are web apps - HTML, CSS, and JavaScript - glued to the glasses by the Even Hub SDK. You build them on your laptop, package them up, and submit them through the dev portal for users to install.

Connection model ​

┌──────────────────┐    HTTPS     ┌────────────────────┐   Bluetooth    ┌─────────────────────┐
│  Even Hub Cloud  │ ◄──────────► │  Phone             │ ◄────────────► │  Even G2 Glasses    │
│  (distribution   │              │  (Even Realities   │                │  (display + input)  │
│   & hosting)     │              │   App + WebView)   │                │                     │
└──────────────────┘              └────────────────────┘                └─────────────────────┘
  • The phone runs the Even Realities App (Flutter), which hosts your plugin in a WebView - Chromium on Android, WKWebView on iOS. Your app logic runs inside that WebView. The Even Realities App relays everything to and from the glasses over Bluetooth.
  • The glasses render UI containers and emit input events - presses, scrolls, swipes. Apart from native scroll handling, no app logic runs on them.

Network whitelist is not a CORS bypass

The app.json network whitelist is an Even-side permission check - it controls which domains your plugin is allowed to call from the WebView. It does not bypass CORS.

In production, fetch() requires both:

  1. The remote domain listed in your app.json network whitelist, and
  2. Correct CORS headers (Access-Control-Allow-Origin, etc.) returned by that remote API.

APIs that work on localhost but fail inside the WebView are almost always CORS misconfigurations on the remote side, not Even bugs. See Networking for the full request flow and debugging tips.

Testing your app ​

Three ways to run your app during development:

  1. QR sideload - the CLI prints a QR pointing at your local dev server; scan it from the Even Realities App and your app loads on the glasses with hot reload.
  2. Private build - evenhub pack produces an .ehpk; upload it through the dev portal to install on your own devices.
  3. Simulator - preview layouts and exercise logic entirely on your laptop, no hardware needed.

PWA as an alternative ​

If you'd rather stay outside the Even Hub distribution flow, build a Progressive Web App and point users at your hosted URL. You keep full control over distribution and hosting; you also skip the dev portal entirely - no packaging, no review.

The SDK bridge ​

The SDK injects a JavaScript bridge (EvenAppBridge) into the WebView. Your frontend calls into it to drive the display and receive input.

Web → Glasses: your JS calls bridge.callEvenApp(method, params) → WebView bridge → Even Realities App → Bluetooth → glasses.

Glasses → Web: input events travel Bluetooth → Even Realities App → window._listenEvenAppMessage(...) → your callback.

For the project layout and a working scaffold, see Your First App § Project structure.