Those who like to travel far from civilization have long been accustomed to using the Iridium system. It is an international satellite network that provides telephony and data transmission where communication towers have never existed and are unlikely to ever appear. It has only two drawbacks: the cost of connection and the fact that ordinary smartphones do not support it.
Nothing can be done about the price of the service; you have to pay for comfort or communication for the sake of survival. As for the technical side of the issue, it is relatively easy to solve with the help of the commercial product Iridium GO. The kit includes a base station, a charger for AC power grids with a set of adapters, a carrying container. The station connects to any smartphone and uses it as an input-output device.
The basic version of Iridium GO costs $ 699, the extended version is $ 1095. It additionally includes a solar panel, several spare batteries and a PC charging module. On a single charge, the system works 15.5 hours in standby mode and 5.5 hours in talk mode. In addition to phone calls, you can work in social networks, upload photos, use e-mail, determine coordinates, launch navigation applications. And, of course, alarms - the safety of travelers is the main goal of this system.