Originally Posted by
Burton
The problem with any and all of these is that they only work where there's reception, which usually means in rural areas and hilly areas - you could be left high and dry. (Regardless of the 'coverage area' indicated by suppliers). So check things out well ahead of time and have a 'plan B' available if necessary.
This would be helpful except that it isn't quite true.
The standard mapping programs usually download maps as needed ("online" maps). That requires cell-reception.
There are numerous apps that download maps beforehand ("offline" maps). That would be your "plan B".
The big problem is usually limited battery life.