Abstract: A first terminal shares a digital marker edited in a digital marker editing mode and an object corresponding to the edited digital marker with a second terminal using a wireless communication technology. If a digital marker is displayed on an image display unit of the first terminal, the second terminal photographs the digital marker using a camera, and synthesizes an object corresponding to the photographed digital marker with a real-time video image obtained through the camera to display a merged image as augmented reality. Then, the second terminal receives input information for changing the digital marker from a user, and transmits the received input information to the first terminal. The first terminal changes a digital marker using the input information received from the second terminal. The second terminal photographs the changed digital marker, and displays an object corresponding to the changed digital marker.