1. A computerized device, comprising: a display adapter; and a data processing hardware element, wherein the data processing hardware element implements a timeline view module to provide output via the display adapter to display a timeline of an application that includes activity that occurs over time during execution of the application, the timeline comprising a plurality of tracks and a plurality of cells, each track providing a temporal view of a respective media component of the application by populating a plurality of cells extending in a first direction in the timeline, wherein the tracks are adjacent in a second direction in the timeline so that cells adjacent in the second direction correspond to activity that occurs at the same time, wherein the plurality of tracks comprise a track corresponding to a plurality of media components of the application, a scripting track providing a temporal view of scripting components of the application, and a label track, the scripting track comprising an action element representing a portion of scripting code defining a series of discrete operations to be performed at a particular time or keyframe by the application, the particular time or keyframe identified by a position of the action element on the timeline, the label track including a label associated with the keyframe of the timeline, the data processing hardware element configured to receive a selection of a cell of the timeline to define or edit the label to be associated with a selected keyframe of the timeline, wherein the label is used by the scripting code.