> For example, AR glasses could stop you from crossing the street when there is an oncoming car, regardless of what the traffic lights indicate.
Not sure this is the best example: Maybe turning off the AR and using your eyes and ears would work better.
Killer app for me is having the manual about an item I use embedded in a qrcode on the item itself, instead of in a paper book or online.
(Not anti-AR by any means - have been working with it/thinking about it since ~1998)
To me the killer app is when the Guardian Angel says "don't eat that" or "don't buy that: it's full of dangerous chemicals".
The real killer app would be the Guardian Demon, which overrides all the good stuff.
"Mmm... doesn't that ice cream look SO good?!"
"It's 3:30 and you've already worked so hard. That bottle is calling your name."
"Yeah, she might be a bit crazy, but YOLO..."
A guardian angel to keep you alive is perhaps the killer app for AR/VR glasses. The AR glasses might even be optional.
hopefully your brain provides this function already!
As Darwin once said, natural selection is that sublime mix of random mutations and expensive glasses.
> AR glasses could stop you from walking alone at night or passing through a high-crime area
Oh dear, this is going to be controversial.