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.

Definitely shows a lot of potential.

An automatic emergency call system is mandatory for new cars in the EU by march 2018. The call works via cell phone technology and is depended on reception the position is determined via GPS. If the system is triggered the car is called by the coordination center for assessing the situation. If the user does not cancel, a response team is sent. The system will usually also have a manual switch for the emergency call.
This may also be useful when people start to help at the scene of the accident and forget to call emergency response.

I bought a new minivan for my wife and it has a setting (enabled by default) that automatically calls for help if a phone is connected (via Bluetooth, Apple CarPlay or Android Auto) and a crash is detected.

As I recall, the OnStar service that GM had years ago would "phone home" if a vehicle's airbags deployed, and the call centre would direct 911 to the location.

GM vehicles still come with OnStar. A friend's son's life was likely saved when he got into an accident in a remote part of Minnesota and OnStar summoned help immediately when he didn't respond to their call after the air bags deployed.

Hope most new systems will be free of use (emergency call are free, so that should be possible); I have seen subscription-based systems with emergency calls as an option.

Any chance these systems can be retrofitted to older rigs? Might be worthwhile....

These systems are intgrated into the car system. They use car sensors (and probably computing power as well) for detecting and evaluating a crash. Hence they would require firmware updates for the older rig. With good luck an existing eletric interface may be useable. If your rig does not feature updateable firmware, you might be out of luck.

Note that I am not a real engineer and so I'm speaking as a semi-informed amateur.

Modern cars all have a Controller Area Network Bus (CAN Bus) or something very much like it, where events are sent from sensors and commands are sent from controller modules. There may (or may not be) also a Local Interconnect Network Bus (LIN Bus) for non-critical systems such as climate control and "infotainment" systems.

The CAN Bus architecture is remarkably similar to Ethernet.

There are sensors within the car, typically accelerometers built into microchips. I believe that those sensors are wired directly into the ECUs for the various airbags rather than sending events over the CAN Bus. Once the sensors send events, the ECU for the airbag(s) the sensor is wired to evaluates the signals and compares them to stored values for "this is a crash the indicates this specific airbag should be inflated." Once that ECU fires the airbag inflator, it sends events indicating the inflation over the CAN Bus to OnStar or the competing system, which then initiates contact with the call center. Seatbelt pretensioners will also fire, with (I believe) the airbag ECU instructing the seatbelt ECU to do so (rather than being the same ECU).

Integrating these devices, systems and programming correctly into a car that doesn't have them from the manufacturer would almost certainly be more expensive than buying the new car. The programming effort alone would be pretty epic.

Thats basically what hum does. The onstar device that has been in GM vehicles for the last decade or so is simply another device connected to the data bus and monitors for the airbag deploy message.

hum does the same, just plugs into the ODBII port which is a direct connect to the data bus as well and listens for the messages.

Onstar is bidirectional and can send messages on the bus such as unlock the doors or start the engine where I believe hum is read only only looks for accident related messages.

Correct me if I'm wrong, folks ...

I thought OnStar was (and is?) a subscription service. You pay a monthly/annual fee, but the hardware is integrated into the car. It is designed to survive a crash, and do its thing.

I get the impression that other "phone home" services under discussion here are "if you own the car, you have the service..."

Except, the kicker is that this service must be "linked to Bluetooth" -- the services rely on the phone that you already own.

And from what I've seen, that phone is loose in the car for a majority of users, and would be nothing more than a projectile/shrapnel in a serious crash.

So, is the "super clever feature" nullified by the basic natural tendencies of the naked ape?

It wouldn't be that great of a challenge to have an aftermarket accelerometer and ROM mounted to the chassis, and connected via bluetooth to a phone. If the accelerometer detects a crash (so many m/s^2 for so many ms) it instructs the phone to place a preprogrammed call.

If the phone is clipped into a mount, it probably won't survive the crash, slamming around the cabin. But, if it's in a pocket or purse, it probably will.

Many smartphones have accelerometers inside. I’m sure some app developer could make an app that would detect when you’re driving and program it to detect that sudden deceleration/stop/crash and dial 9-1-1. My phone rides shotgun in airplane mode. It wouldn’t be much use.

My phone is not much better; data services are turned off almost all the time, unless I have a specific task that I require of them.

The current trend of turning a phone into the equivalent of a desperately helpless infant that requires your constant attention is a sucker's game, selling advertising for soothers I do not need.

Though if my accelerometer detected dangerous G's, and sent a text to someone who could respond, I would not object. In theory, that could work. In practice, the alert would be preceded by ads for trusses, wheelchairs, autobody work, and ambulance chasing lawyers.

My dashcam app (Hovans Autoguard?) will do that. If it senses an impact, it will archive the video clip. But, there's the previously mentioned problem of survivability after an accident.

What happens when you drop your phone while driving