API Reference > imodeljs-frontend > IModelApp IModelApp Classes for configuring and administering an iModel.js application. See the learning articles. Classes Name Description IModelApp Global singleton that connects the user interface with the iModel.js services. WebViewerApp The frontend of apps with a shared backend for visualization of iModels. Beta Constants Name Description iModelJsCss Interfaces Name Description FrontendSecurityOptions Options that can be supplied with IModelAppOptions to customize frontend security. IModelAppOptions Options that can be supplied to IModelApp.startup to customize frontend behavior. WebViewerAppOpts Options for WebViewerApp.startup Beta Last Updated: 29 November, 2022