A few years ago, I had headed out of the Campsite in Langdale aiming my merry way to Scarfell Pike, when I got to Esk hause, I decided to make a brew. When I was sitting there admiring the view, a young guy arrived looking a tad worried.
When I asked what the problem was “the batteries” in his GPS had died, that’s no problem is say to him put your spare batteries in ; “no spare batteries, no paper map, and no compass” or survival or first aid kit. And he was planning to go to Scarfell. But being a nice old chap I guided him to the Top of Scarfell and lectured him on his errors.
When I cycle or walk I use the gps firstly to log my route, and secondly if in the mountains and it hard to get a fix on the paper map due to cloud, fog etc. I use the GPS.
In Car I find them annoying, as they Yap, yap away trying to get you to turn into one way streets, often sending one the long way round to your finish point.