1. A user equipment to provide an augmented reality (AR) service, the user equipment comprising: a photographing unit to capture an image of a target object; an information collecting unit to collect contextual information of the captured image of the target object, the contextual information comprising a location information of the photographing unit and a first azimuth information between the target object and the photographing unit; a tag generating unit to generate an AR tag based on a first direction, the AR tag corresponding to the contextual information; and a display unit to display the captured image of the target object and the AR tag.