A computerized device can comprise a display adapter and a data processing hardware element, such as a processor. The data processing hardware element implements a timeline view module to provide output via the display adapter to display a timeline of an application under development. The timeline can comprise a plurality of tracks, including a track providing a temporal view of each of a plurality of media components of the application and a scripting track providing a temporal view of scripting components of the application. The scripting track can be rendered and populated by default by the timeline view module, and can be kept in view even when other tracks are scrolled out of view. The timeline view module can respond to input events directed to the scripting track to define scripting actions such as labels and actions used to control the application.