It was interesting to read about people being led by their GPS into a desolate national park because the Apple Maps application erred in the location of Mildura (see report here). There's been a lot of publicity about the troubles with Apple's maps, which I would have thought would put users on notice to be careful. However, even if the particular issue with Apple is put to one side, it strikes me as strange that people become so reliant on their GPS that they're prepared to turn off sealed and well sign-posted highways on to sandy tracks just because their GPS tells them to do so!
I invested in a GPS some time back to see how it worked. As a trial, I used it for a while on routes with which I am familiar, to see how it compared with my own knowledge. Yes, on one occasion it suggested a route that offered a better option than I had thought of. However, by and large I became frustrated with it because it insisted that I use busier roads, which often involved tram lines and shopping strips and the need to make turns at congested intersections. The routes I chose from experience, on the other hand, while still on main roads (and involving no greater distance), generally provided a better run. Presumably the technology can only improve, but based on my experience (and that of Apple users, perhaps?), it seems there's still a way to go.
I still keep the GPS in the car but not switched on, and I admit that it did come in handy on one occasion when I became disorientated. However, my first recourse is to the street directory or a map!
Edit: Here's another GPS story - http://www.abc.net.au/news/2012-12-16/gps-fail-man-caught-driving-wrong-way-on-freeway-blames-gps/4430364