You can chat with any other goTenna Mesh user within range. The reason you can't chat with people who don't have goTenna Mesh is due to the physics of radio waves. You need a properly designed RF receiver to interpret a goTenna Mesh signal. We would love to have our signals get to devices that aren't goTenna-enabled, but phones are designed to work with towers and wifi — exactly what we are working around — and regular radios aren't able to operate at the level of our super-smart networking protocols. We should also point out that goTenna Mesh devices will not be interoperable with regular goTenna devices because they operate on different frequencies.
With that said, the goTenna Plus app upgrade enables an SMS network relay feature, so you can reach people beyond your off-grid network. If a goTenna Mesh user nearby has cell service, they can transmit your message via SMS to your intended recipient.