Portable multifunction device, method, and graphical user interface for interacting with user input elements in displayed content

A device with a touch screen display displays an electronic document that includes a respective user input element. The device detects a first input that corresponds to selection of the respective user input element that is displayed with text having a first size. In response to detecting the first input, the device enlarges the respective user input element, moves the respective user input element toward a center of a first portion of the display and displays an input interface for selecting input for the respective user input element in a second portion of the display that is different from the first portion of the display. The input interface includes a plurality of text input choices for entering text that are displayed at a second size larger than the first size. The device uses text that corresponds to a selected text input choice as input for the respective user input element.