A system for navigating among a plurality of windows representing activities in a computing device, comprising: a processor for running at least two activities concurrently; a display screen, coupled to the processor, operable by the processor in at least a full-screen mode and a windowed mode, wherein the processor is operable: in the full-screen mode, to control the display screen to display an interface for a single one of the activities; and in the windowed mode, to control the display screen to display a first window on the display screen and corresponding to a first activity and, adjacent to the first window, a portion of at least a second window corresponding to at least a second activity, wherein the first and second windows are displayed adjacent to one another in a positional sequence along a horizontal axis; and an input device, coupled to the processor, for accepting user input, wherein the processor is responsive to a first user input to control the display screen to toggle between the full-screen mode and the windowed mode and, in the windowed mode, responsive to a second user input to control the display screen to shift the positions of the windows of the display screen while the windows remain in the positional sequence so that the second window becomes more visible on the display screen and the first window is at least partially visible on the display screen, and responsive to a third user input to close the first window and end the first activity, the third user input comprising the user moving the first window upward off of the display screen. a processor for running at least two activities concurrently; a display screen, coupled to the processor, operable by the processor in at least a full-screen mode and a windowed mode, wherein the processor is operable: in the full-screen mode, to control the display screen to display an interface for a single one of the activities; and in the windowed mode, to control the display screen to display a first window on the display screen and corresponding to a first activity and, adjacent to the first window, a portion of at least a second window corresponding to at least a second activity, wherein the first and second windows are displayed adjacent to one another in a positional sequence along a horizontal axis; and an input device, coupled to the processor, for accepting user input, wherein the processor is responsive to a first user input to control the display screen to toggle between the full-screen mode and the windowed mode and, in the windowed mode, responsive to a second user input to control the display screen to shift the positions of the windows of the display screen while the windows remain in the positional sequence so that the second window becomes more visible on the display screen and the first window is at least partially visible on the display screen, and responsive to a third user input to close the first window and end the first activity, the third user input comprising the user moving the first window upward off of the display screen. in the full-screen mode, to control the display screen to display an interface for a single one of the activities; and in the windowed mode, to control the display screen to display a first window on the display screen and corresponding to a first activity and, adjacent to the first window, a portion of at least a second window corresponding to at least a second activity, wherein the first and second windows are displayed adjacent to one another in a positional sequence along a horizontal axis; and an input device, coupled to the processor, for accepting user input, wherein the processor is responsive to a first user input to control the display screen to toggle between the full-screen mode and the windowed mode and, in the windowed mode, responsive to a second user input to control the display screen to shift the positions of the windows of the display screen while the windows remain in the positional sequence so that the second window becomes more visible on the display screen and the first window is at least partially visible on the display screen, and responsive to a third user input to close the first window and end the first activity, the third user input comprising the user moving the first window upward off of the display screen.