A method of updating a dynamic input and output device, the method comprising: at a computing system comprising one or more processors, a primary display, memory, and a housing at least partially containing a physical input mechanism comprising a plurality of physical keys, the housing containing a touch screen display adjacent to the physical input mechanism, wherein the housing is separate and distinct from the primary display: displaying a first user interface on the primary display, the first user interface comprising one or more user interface elements; identifying a user interface element that is in focus among the one or more user interface elements on the primary display; determining whether the user interface element that is in focus on the primary display is associated with an application executed by the computing system; and, in accordance with a determination that the user interface element that is in focus on the primary display is associated with the application executed by the computing system, displaying a second user interface on the touch screen display, including: a first set of one or more user interface elements corresponding to the application; and at least one system-level user interface element corresponding to at least one system-level functionality, wherein a user may select a particular one of the one or more user interface elements corresponding to the application or the at least one system-level user interface element by touching a location on the touch screen display that corresponds to the particular one of the one or more user interface elements corresponding to the application or the at least one system-level user interface element, wherein the method further comprises: detecting a user input at a new user interface element on the primary display, the new user interface element being associated with the application executed by the computing system and in response maintaining display of the at least one system-level user interface element in the second user interface on the touch screen display and displaying in the second user interface on the touch screen display a second set of one or more user interface elements corresponding to the application, the second set being distinct from the first set. at a computing system comprising one or more processors, a primary display, memory, and a housing at least partially containing a physical input mechanism comprising a plurality of physical keys, the housing containing a touch screen display adjacent to the physical input mechanism, wherein the housing is separate and distinct from the primary display: displaying a first user interface on the primary display, the first user interface comprising one or more user interface elements; identifying a user interface element that is in focus among the one or more user interface elements on the primary display; determining whether the user interface element that is in focus on the primary display is associated with an application executed by the computing system; and, in accordance with a determination that the user interface element that is in focus on the primary display is associated with the application executed by the computing system, displaying a second user interface on the touch screen display, including: a first set of one or more user interface elements corresponding to the application; and at least one system-level user interface element corresponding to at least one system-level functionality, displaying a first user interface on the primary display, the first user interface comprising one or more user interface elements; identifying a user interface element that is in focus among the one or more user interface elements on the primary display; determining whether the user interface element that is in focus on the primary display is associated with an application executed by the computing system; and, in accordance with a determination that the user interface element that is in focus on the primary display is associated with the application executed by the computing system, displaying a second user interface on the touch screen display, including: a first set of one or more user interface elements corresponding to the application; and at least one system-level user interface element corresponding to at least one system-level functionality, a first set of one or more user interface elements corresponding to the application; and at least one system-level user interface element corresponding to at least one system-level functionality, wherein a user may select a particular one of the one or more user interface elements corresponding to the application or the at least one system-level user interface element by touching a location on the touch screen display that corresponds to the particular one of the one or more user interface elements corresponding to the application or the at least one system-level user interface element, wherein the method further comprises: detecting a user input at a new user interface element on the primary display, the new user interface element being associated with the application executed by the computing system and in response maintaining display of the at least one system-level user interface element in the second user interface on the touch screen display and displaying in the second user interface on the touch screen display a second set of one or more user interface elements corresponding to the application, the second set being distinct from the first set.