This is the Btech UV-Pro. It is a ham radio that can send APRS text messages. (About $160)
It comes with its own app that works pretty good but another app call APRSDroid is a little more developed and functional for APRS.
Here I have sent some messages (green text) to an automated bot that can respond and send data back to you.
APRSDroid also has a map view to see the location of other users that have chosen to beacon out their location (you can turn this feature off, display a static location of your choosing or a level of ambiguity).
APRS works completely without the internet but you can use it over the internet (
aprs.fi) and to send text messages to normal cell phone users.
I am currently running a digipeater (APRS repeater) using the Digipi set up.
digipi.org/
Here is my Digipi using a Digirig and KG-UV8H for the radio. It is hooked up to a roof J-Pole antenna.
This digipeater allows my handheld unit to connect with other many miles away. You only need one of these if there are none in your area.
I am happy to help any who want to know more about this set up.