An electronic device, with a touch-sensitive surface and a display, includes one or more sensors to detect intensity of contacts with the touch-sensitive surface. The device detects a contact on the touch-sensitive surface while a focus selector corresponding to the contact is at a respective location on the display associated with additional information not initially displayed on the display. While the focus selector is at the respective location, upon determining that the contact has an intensity above a respective intensity threshold before a predefined delay time has elapsed with the focus selector at the respective location, the device displays the additional information associated with the respective location without waiting until the predefined delay time has elapsed; and upon determining that the contact has an intensity below the respective intensity threshold, the device waits until the predefined delay time has elapsed to display the additional information associated with the respective location.