A computer-implemented method is performed at a multifunction device with a display and a touch-sensitive surface. The method includes detecting multiple input gestures by a user, beginning with an initial input gesture. For each input gesture after the initial input gesture, the method scrolls information on the display at a respective scrolling speed. The respective scrolling speed is determined based on the respective input gesture movement speed in the input gesture and a movement multiplier. The method determines whether the respective input gesture meets one or more swipe gesture criteria, and determines whether the respective input gesture meets one or more successive gesture criteria. When the input gesture meets the one or more swipe gesture criteria and the one or more successive gesture criteria, the method updates the movement multiplier in accordance with one or more movement multiplier adjustment criteria.