1. An apparatus for performing multi-tasking in a portable terminal, the apparatus comprising: a display for displaying an application-containing image in which at least one specific image representing at least one application running in a background is contained and arranged; and a controller for operatively displaying the at least one specific image representing the at least one application running in the background, so as to be contained in the application-containing image, and for controlling the at least one application running in the background by controlling the at least one specific image based on a specific gesture, wherein when a touch-and-drag to the left/right occurs on the application-containing image or the at least one specific image contained in the application-containing image, the controller operatively displays information provided by the application while sequentially expanding in the drag direction the at least one specific image representing the at least one application running in the background, during the occurrence of the drag.