An interactive iTwin.js app has two components or layers:
Simple Viewer App is a complete example of an interactive app.
See the frontend learning articles.
Some apps can use an already deployed Web service. In that case, there is no need to write a backend. Just write the frontend's main to point to the remote service.
Note that the backend of an interactive app typically does not open an iModel on its own initiative. Instead, the app frontend will ask the backend to open an iModel, and then the frontend will pass the resulting IModelRpcProps to methods of the backend. The backend should therefore always initialize the IModelReadRpcInterface.
An interactive app must be tailored to match each desired configuration and sometimes each target platform. It must then be packaged and deployed using appropriate tools. For more information, see:
Last Updated: 15 June, 2021