When Tropical Cyclone Debbie hit Queensland last week, one of the casualties was the region’s mobile phone network. Phone towers can stop working because they have been damaged by the wind, or because they have run out of diesel to run their generators.

Whatever the cause, the end result is the same: a number of people will find their mobile phones not connected to the network, leaving them without communications for an extended period of time. Here's how to stay connected in times of need.