A method for navigating between user interfaces, comprising: at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensities of contacts with the touch-sensitive surface: displaying, on the display, a user interface for an application; detecting an edge input that includes detecting a change in a characteristic intensity of a contact proximate to an edge of the touch-sensitive surface; and, in response to detecting the edge input: in accordance with a determination that the edge input meets system-gesture criteria, performing an operation that is independent of the application, wherein: the system-gesture criteria include intensity criteria; the system-gesture criteria include a location criterion that is met when the intensity criteria for the contact are met while the contact is within a first region relative to the touch-sensitive surface; and the first region relative to the touch-sensitive surface is determined based on one or more characteristics of the contact, wherein the change in the characteristic intensity of the contact proximate to the edge of the touch-sensitive surface is detected at a location that corresponds to an operation in the application; and in response to detecting the edge input: in accordance with a determination that the edge input meets application-gesture criteria and does not meet the system-gesture criteria, performing the operation in the application instead of performing the operation that is independent of the application. at an electronic device with a display, a touch-sensitive surface, and one or more sensors to detect intensities of contacts with the touch-sensitive surface: displaying, on the display, a user interface for an application; detecting an edge input that includes detecting a change in a characteristic intensity of a contact proximate to an edge of the touch-sensitive surface; and, in response to detecting the edge input: in accordance with a determination that the edge input meets system-gesture criteria, performing an operation that is independent of the application, wherein: the system-gesture criteria include intensity criteria; the system-gesture criteria include a location criterion that is met when the intensity criteria for the contact are met while the contact is within a first region relative to the touch-sensitive surface; and the first region relative to the touch-sensitive surface is determined based on one or more characteristics of the contact, displaying, on the display, a user interface for an application; detecting an edge input that includes detecting a change in a characteristic intensity of a contact proximate to an edge of the touch-sensitive surface; and, in response to detecting the edge input: in accordance with a determination that the edge input meets system-gesture criteria, performing an operation that is independent of the application, wherein: the system-gesture criteria include intensity criteria; the system-gesture criteria include a location criterion that is met when the intensity criteria for the contact are met while the contact is within a first region relative to the touch-sensitive surface; and the first region relative to the touch-sensitive surface is determined based on one or more characteristics of the contact, the system-gesture criteria include intensity criteria; the system-gesture criteria include a location criterion that is met when the intensity criteria for the contact are met while the contact is within a first region relative to the touch-sensitive surface; and the first region relative to the touch-sensitive surface is determined based on one or more characteristics of the contact, wherein the change in the characteristic intensity of the contact proximate to the edge of the touch-sensitive surface is detected at a location that corresponds to an operation in the application; and in response to detecting the edge input: in accordance with a determination that the edge input meets application-gesture criteria and does not meet the system-gesture criteria, performing the operation in the application instead of performing the operation that is independent of the application.