User Tracking Methods for Augmented Reality

Augmented reality has been an active area ofresearch for the last two decades or so. This paper presents acomprehensive review of the recent literature on trackingmethods used in Augmented Reality applications, both forindoor and outdoor environments. After critical discussion ofthe methods used for tracking, the paper identifies limitations ofthe state-of-the-art techniques and suggests potential futuredirections to overcome the bottlenecks.