1. A computer implemented method for extending a visualization platform, the method comprising: providing, by a computing device comprising hardware, a visualization authoring environment configured to enable a first user to define a user interface appearance and behavior of a prospective software application for at least a smart-phone or a prospective modification to an existing software application for at least a smartphone at least in part by incorporating native widgets; storing such definitions on computer readable media in a format that can be utilized by one or more other instances of the visualization authoring environment or one or more instances of a visualization rendering environment, or both one or more other instances of the visualization authoring environment and one or more instances of a visualization rendering environment; providing, by the computing device, in the visualization authoring environment a facility to enable a user to incorporate one or more non-native widgets into the visualization authoring environment without requiring acquisition or installation of a new version of the visualization authoring environment; enabling the first user to search for native and non-native widgets using the computing device; providing, by the computing device, in the visualization authoring environment a facility to enable the first user to incorporate non-native widgets into a visualization project for a prospective software application for a smartphone or a prospective modification to an existing software application for a smartphone; providing, by the computing device, in the visualization authoring environment a user interface component configured to display icons corresponding to one or more non-native widgets and one or more native widgets and process click and drag operations to add widgets to the visualization project; providing, by the computing device, in the visualization authoring environment a user interface component configured to accept user inputs to modify the properties of one or more widgets; providing, by the computing device, in the visualization authoring environment a user interface component configured to display comments made by a second user; providing, by the computing device, in the visualization authoring environment a facility to enable the first user to modify one or more of attributes of an instance of a non-native widget, including at least: size and position; and enabling the first user to simulate the visualization project for a prospective software application for a smartphone or a prospective modification to an existing software application for a smartphone using the computing device.