If (a big 'if', ofc) you handwave all the display, compute and cost issues better, AR is a no-brainer even simply as a better alternative to tablet and smartpho

If (a big 'if', ofc) you handwave all the display, compute and cost issues better, AR is a no-brainer even simply as a better alternative to tablet and smartphone displays. Screen-on-a-handheld-box displays are trapped in inescapable trade-offs—screen too small, device too big, screen too close to the eyes, choose one; screen at a low angle, device hanging from a fastener contraption, auxiliary display in use, gorilla arm, choose one—that HMDs are not trapped in. Going beyond that to 'real' AR applications, maps applications alone are enough to justify AR. Turn-by-turn on-foot navigation and local points of interest are use-cases which cry out for head-up display instead of forcing the user to divine information from a small handheld map (and audio cues etc.) Alternatively the user could do flatscreen AR by gorilla-arming their phone, but it's obvious why using a sufficiently good AR HMD is preferable to this. The big extra stumbling block here is once again technology—the coverage, accuracy, and speed of tracking with GPS etc.—not inherent uselessness.