1. An interactive model development system comprising: at least one computing device; and a non-transitory computer-readable medium having computer-executable instructions stored thereon that, if executed by the at least one computing device, cause the at least one computing device to perform operations comprising: providing a plurality of primitives for use in developing an interactive representation model of a proposed software application; providing a first user interface for display via which a user can select a primitive from the plurality of primitives, drag the selected primitive to a desired location in an interactive representation model design area, and drop the primitive at the desired location in the interactive representation model design area; in response to the user's selection and dragging of a first primitive to a first location in the interactive representation model design area, causing the first primitive to appear at the first location; providing a second user interface for display via which the user can edit properties associated with a primitive selected by the user from the interactive representation model design area; in response to the user's editing of a first property associated with the first primitive, associating the edited first property with the first primitive; enabling members of a team to access and modify the interactive representation model via respective user interfaces of the interactive model development system; enabling members of the team to conduct an online discussion regarding the interactive representation model, wherein the online discussion is recorded as a threaded discussion for later access by one or more users; storing and reporting status for a plurality of team tasks related to development of the interactive representation model of the proposed application; generating a browser readable format of the interactive representation model of the proposed application in accordance with inputs received via one or more of the first and second user interfaces.