Have you ever gotten struck outdoors and realized your phone gets no signal? That could be very frustrating. goTenna is designed to solve that issue. It pairs wirelessly with your smartphone, enabling you to text and share your location with anyone who has the device. There are not satellites or towers required for this cool product to work.
The idea here is simple: with goTenna, you can go off-grid and always have a way to share your location with others. If you are taking a trip as a team, you can use this solution to stay in touch with other team members and find them when separated. goTenna is a small and rugged device, so you can carry it around easily. It is end to end encrypted, which is a plus. The companion app lets you send and receive messages for free, share location, broadcast to anyone within range, chat with others, and more. The device is compatible with iOS and Android devices. Sets you back $149.99 per pair at the time of this writing.[Source]