I just came across an advertisement for this product called Hum, and I thought that it has an interesting potential in an emergency:

https://www.hum.com

It appears to be able to detect an accident, and then it can summon help for you. It's not clear to me whether it always requires your verbal approval.

I have driven through places like Wyoming where there is just nothing for miles and miles, and there is also little traffic. If you get into a bad accident and, say, lose the ability to summon for help (perhaps because you are unconscious), this item seems like it may be useful. I am guessing Hum is based on cell phone technology, and so if you don't have reception, you still may be up the proverbial creek.