There's many, many potential uses for this approach.
Doctors could monitor a patient's vitals and view an x-ray or CAT image over the area they are operating on, emergency workers could see a map of a building's interior, which tells them where to go to get around obstacles or even where people are trapped, business people and politicians could access public details of individuals they meet so they're never short of a name or small talk, street workers could view all the conduits under a road, or builders the wires and pipes in walls and floors in order to guide their activities.
Even tourists could use AR productively, viewing historical information on landmarks and tour routes as they travel around a city or country.
The potential for global information at one's eyeballs may even be a more profound leap forward than the internet's now established concept of global information at one's fingertips.
This isn't even new technology. Our grandparents were the first to have access to augmented reality devices, before computers, microwave ovens or mobile phones, albeit in a limited way.
The first HUD was invented in 1937, when the German air force developing the reflector sight, an approach that used mirrors to reflect a gunsight modified by airspeed and turn rate onto the glass in front of a fighter pilot's eyes. This improved their accuracy and effectiveness in air combat and began a race by other nations to develop similar approaches.
However the first electronic HUD wasn't created until the mid 1950s, when the British introduced the Blackburn Buccaneer, a low-flying bomber with the world's first inbuilt HUD. While the prototype flew in 1958, the production aircraft didn't enter service until 1968 and served until 1994, used as late as in the Gulf War.
It was noticed that the HUD improved the general abilities of pilots, despite being originally for targeting purposes only, and it was expanded to provide a range of additional information to help pilots.
The modern HUD was developed by 1975, by a French test pilot, featuring a standard interface to aid pilots switching between planes. Around the same time HUDs were first expanded into use on civilian planes and in 1988 the Oldsmobile Cutlass Supreme became the production car to feature a HUD, followed around ten years later by the first motorcycle helmet offering a heads-up display.