1. A method of controlling data displayed by a dual-screen device, comprising: receiving a first user input gesture that corresponds to instructions to maximize a display of a first application displayed on a first screen of the dual-screen device; determining, according to the first user input gesture and maximization rules for the first application, a first display configuration for the first application; based on the first display configuration for the first application, causing data from the first application to be simultaneously displayed on both the first screen and a second screen of the dual-screen device in accordance with the first display configuration; receiving a second user input gesture, different from the first user input gesture, that corresponds to instructions to maximize a display of the first application displayed on the first screen of the dual-screen device; determining, according to the second user input gesture and the maximization rules for the first application, a second display configuration for the first application, wherein the second display configuration is different from the first display configuration; and based on the second display configuration for the first application, causing data from the first application to be simultaneously displayed on both the first screen and second screen of the dual-screen device in accordance with the second display configuration.