The user interface makes no difference between development tool and application. As a developer you have access to the DataView development tools (manager toolbars, system masks, etc.) after starting the client. They are used to define the objects of the application (meta-data) and manage them. At the same time you can work with existing interaction objects (top menus, toolbars, application-specific masks, etc.) as the future users of the application will when you manage your own detente data (user data).