Augmented Reality (AR) is a term used to describe the use of technology to superimpose images, data or other content over a displayed real life view of the world. Most applications for AR have been either industrial/military or home computer-based. But recently, innovative technologists and developers have untethered AR by leveraging mobile networks and, as a primary device, smartphones. This shift into the mobile use of AR radically changes the paradigm of AR and propels AR far beyond the capacity, possibilities and opportunities of tethered uses. Mobile AR will expand rapidly, driven by smartphone apps, then even more rapidly as developers take advantage of AR platforms/engines that enable them to embed AR functionality into the broad base of smartphone apps. This study examines the drivers and barriers involved in mobile AR, identifies key opportunities for potential players and outlines the core business cases. Critical forecasts include revenue and app downloads.