How many cell phone users in the world were there in 1985?

Augmented reality headsets? Not Google Glass, necessarily, but something like it.

In the UK one of our main mobile phone retailers wasn’t even founded until 1989 and it was called Carphone Warehouse.

I think I first saw a carphone in summer 1988 (may have been '87) when I was on a hang gliding course in the Peak District and another person on the course had one with all the workings in the boot (trunk) of his car. He was happy showing it off and calling his office, but the rest of us wondered why he couldn’t just take a break from work for a few days like the rest of us!