In Colorado, it is not unusual to not have cell phone service in many foothills and mountain locations. This can be a very dangerous situation.
Case in point, a couple of days ago local rider Barb Schultz told me a story about her neighbor Chad (don't have Chad's last name). He was mountain biking on a local trail when he sustained a serious injury to his upper leg. The short story is that the front fork on his mountain bike suffered catastrophic failure. The break ended up slicing his upper leg wide open.
Chad was only a quarter of a mile from the ranger station when the accident occurred, but he had no cell coverage and couldn’t call for help. Luckily, Chad is a medical student and knew how to take care of himself until he could walk out of the single track and get help. He used his jersey as a tourniquet to stop the bleeding. He did get help and eventually received 32 stitches in his "fillet gash" to repair the injury.
Barb told me that Chad’s story is one good reason why she carries something called SPOT. It is an emergency response system that uses satellites (not cell towers) to call for help when you really need it. I hadn’t heard of it before.
Barb uses the personal tracker (I think) although there are options to have the application downloaded to your smart phone. The service plans can be found here.
Because Barb frequently rides alone, her husband can watch her on the website and know where she is and if she’s still moving along at the expected rate.
I’m often on trails and roads, with and without other people, where there’s no cell coverage. There have been two occasions I can think of where someone was injured and no one in the group had cell coverage. We were able to get help by riding out to a car or to phone coverage, but having an emergency response option would have been great.
I’m currently investigating the various options.