http://www.foxnews.com/tech/2014/04/03/new-app-looks-to-give-smartphone-owners-ability-to-text-without-service-or/ (http://www.foxnews.com/tech/2014/04/03/new-app-looks-to-give-smartphone-owners-ability-to-text-without-service-or/)
so one could look at this and think that voice comm's using mesh networks wouldn't be too hard. combine with gps and you could now where the person your talking to is if needed.
This would work if you've got a mass of devices within range... like a radio, but it would significantly change the footprint of a typical phone now, if the battery and radio have to be upgraded to support ISR like use.
.. OTOH, it would work for many instances where the telcos are racking up charges, where you're in clusters like the mall, nearby vehicles while caravanning, working an activity in semi-close proximity.
Here is something interesting that has been used.
http://en.wikipedia.org/wiki/SPAN_project (http://en.wikipedia.org/wiki/SPAN_project)
though to make it works you have to root the phone and recompile the linux kernel. Still imagine it as a blue force tracker on your phone. They have some a bft that is used for airsoft, however it requires access to the cell network to get to their servers.
Intriguing, but I have to wonder about the safety concerns of a text-only messaging application in the field. I can see a situation where somebody trips and breaks something because they were tapping out a status report on their phone.
Simple.
Shoot, move, communicate.
Just like we try to teach people not to walk around with DF antennae out, staring at the needle. (or staring at a compass) doof trips, takes antenna to the eye. Saftey report.
Shoot your bearing. Move to your landmark. Communicate (if necessary)
Repeat.
don't text while driving (er, walking)
also i imagine that a direct hit from a paintball would probably jack a phone pretty good...
not to mention if it's in an outer cargo pocket, getting jumped on by the full weight of the person carrying it...
Ignore. Misread.
There is a voip app for span.
Harris Radio has an app that functions like the old NexTel phones. It basically operates like a radio over the cell network(which is actually a radio) and is in use by some Police agencies on the East Coast.