14. A computer program product comprising a non-transitory computer readable medium embodying program code, the program code comprising: program code for providing a graphical user interface of an application development environment; program code for providing, in the graphical user interface, a timeline view that includes activity that occurs over time during execution of an application under development, wherein the timeline view comprises a plurality of cells and a plurality of tracks, each track providing a temporal view of a respective media element by populating a plurality of cells extending in a first direction in the timeline view, wherein the tracks are adjacent in a second direction in the timeline view so that cells adjacent in the second direction correspond to activity that occurs at the same time; program code for providing, in the timeline view, a default configuration of the plurality of tracks, the default configuration comprising at least one track corresponding to a media element of the application under development, a label track, and a scripting track, the scripting track comprising a visual representation of a scripting 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; and program code for receiving 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.
14. A computer program product comprising a non-transitory computer readable medium embodying program code, the program code comprising: program code for providing a graphical user interface of an application development environment; program code for providing, in the graphical user interface, a timeline view that includes activity that occurs over time during execution of an application under development, wherein the timeline view comprises a plurality of cells and a plurality of tracks, each track providing a temporal view of a respective media element by populating a plurality of cells extending in a first direction in the timeline view, wherein the tracks are adjacent in a second direction in the timeline view so that cells adjacent in the second direction correspond to activity that occurs at the same time; program code for providing, in the timeline view, a default configuration of the plurality of tracks, the default configuration comprising at least one track corresponding to a media element of the application under development, a label track, and a scripting track, the scripting track comprising a visual representation of a scripting 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; and program code for receiving 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. 15. The computer program product of claim 14 , further comprising: program code for responding to an input event designating the scripting track by presenting an interface, the interface configured to display the scripting element.