1. A method of controlling an electronic device with a touch-sensitive display, comprising: detecting contact with the touch-sensitive display while the device is in a user-interface lock state; moving an unlock image along a predefined displayed path on the touch-sensitive display in accordance with the contact, wherein the unlock image is a graphical, interactive user-interface object with which a user interacts in order to unlock the device; transitioning the device to a user-interface unlock state if the detected contact corresponds to a predefined gesture; and maintaining the device in the user-interface lock state if the detected contact does not correspond to the predefined gesture.