Highly recommend this mode of operation. Myself and Phil K6AXY have been actively working each other most evenings as I travel across country. Using Radioddity Dual Band DMR radios GD-77.
We both went with the SharkRF OpenSPOT repeaters. I have mine tied to my AT&T Hotspot Mobile in my motor home.
Works great and have had many QSOs on Talk Group 3100 North America.
Duane
N6DMR
Note: I have had the N6DMR Call Sign for many years, now it is very vogue within the DMR community!
Found a new method of doing private or specific group calls in DMR mode. If you create your own Talk Group (TG) you can Key it active. Anyone else that keys up to that same Talk Group number will be able to chat with you.
They are calling it a Adhoc Talk Group.
I tested this with another Ham, we both created a TG 31000077, once you key it up, you have a private TG. If you want to make it a semi-private multi user group, just give out the TG number to other hams and you all have your own temporary TG.