If the idea of being without mobile phone reception scares the book-face out of you, then the Gotenna Phone Booster is the best thing since the Selfie Stick. Think of the Gotenna like a CB radio but for your phone, as it allows you to make calls or send text messages even when there is no reception, a network is out or you are in crowded areas. You need two of them to communicate between. Alternatively, you can bounce info back and forth to other phones connected to the Gotenna network within an 80km range. That makes for a pretty darn handy addition to anyone glove box, especially if you are out exploring or even just attending a large four-wheel drive show with your kids.
Priced from $195 for a pair
https://gotenna.com/