Abstract: A system and method for creating, testing, deploying, and executing single-page web applications on a client device. The system and method provide an SPA model that includes a user interface, a UI data service, and a set of procedures for communication between the user interface and the UI data service. A runtime can initialize the UI database and a UI data service and render the user interface. Based on a request received through the user interface, the UI runtime allows a copy of the UI database to be modified by the UI data service or the application database getting updated from copy. The runtime can directly update the UI database.