1. A method, comprising: at a multifunction device with a touch screen display: displaying content on the touch screen display at a first magnification, wherein the content includes selected content; detecting a finger contact on a respective end of the selected content; displaying a content magnifier adjacent to the respective end of the selected content, wherein the content magnifier displays: an expanded portion of the content proximate to the respective end of the selected content at a second magnification that is greater than the first magnification, and a boundary marker that denotes a current position of the respective end of the selected content; detecting movement of the finger contact across the touch screen display; updating the respective end of the selected content and the displayed expanded portion of the content proximate to the respective end at the second magnification in accordance with the movement of the finger contact; moving the content magnifier and the boundary marker in accordance with the movement of the finger contact detecting lift off of the finger contact from the touch screen display when a location of the finger contact corresponds to a current position within a current word; and, in response to detecting lift off of the finger contact from the touch screen display when the location of the finger contact corresponds to the current position within the current word: terminating display of the content magnifier; placing the respective end of the selected content at the current position within the current word when the movement of the finger contact is less than a predefined value in a predefined time interval; and placing the respective end of the selected content at a respective end of the current word when the movement of the finger contact is greater than the predefined value in the predefined time interval.