An electronic device, with a display and an input device separate from the display, displays a user interface that includes a representation of a first application and a pointer object. The device receives, at the input device, a user input event directed to a location in the user interface at which the pointer object is displayed. In response to the user input event, when the respective location in the user interface at which the pointer object is displayed is over the representation of the first application, the device provides, to the first application, information that describes a simulated touch event including information that describes locations of one or more simulated touches in the user interface; and displays, on the display, a change in the representation of the first application that is determined by the first application in response to the information that describes the simulated touch event.