By associating more than one control with a given button, multiple controls can be activated and deactivated simultaneously, providing a rich user experience with less button clicking required in order to interact with the application.
For example, in the default application, the following controls are combined into a single 'Navigation' button:
This interaction mode therefore allows the user to pan around with one finger, select features with a single tap and have their properties show up in a popup window, double-tap to zoom in at a specific point, two-finger tap to zoom out, three-finger tap to return to the initial map extent, and pinch in or out with two fingers to zoom in or out on the map.