Drones are not ambulances, this is probably for rural or mountainous areas, better than nothing until help arrives. Smart watches calling emergency services for you based on sensors does happen already though.
From watching British television, at least, I gather that "Brilliant!" usually is akin to American "Cool!" or "That's great!". On the other hand, in the US we would use "brilliant" to describe Albert Einstein (or someone else who is exceptionally intelligent).
I think there's a bit of a nuanced difference in how we use the word "clever" as well. Where you would call someone clever, we would usually say he is smart (or maybe brilliant, if smart enough). "Clever" in the US often has a slightly derogatory sense to it. Someone who is good at solving a Rubik's cube is clever. Yes, it takes a certain intelligence but of a gimmicky sort.
I would say that in the UK we use both, with a different meaning according to context. But yes I agree that "Brilliant!", "Super!", and "Fab!" are all British ways of saying the same thing.