Msmith,
Please allow me to expand on my responses:
I prefer Garmin, whichever Amazon has on sale with lifetime maps of the appropriate sized screen.
But there is a real application for the tablets, properly mounted (again Amazon).
I have found where you do not have cellular telephone service there are few highway intersections, and thus little to no need to turn or need direction. Cell service gaps are almost always in low population areas, with fewer people there are less roads, less roads equals fewer turns or highway changes. There are places in Canada where your next prompt is 800 miles away. Even with my limited capacity, I do not need constant reinforcement. I usually can remember a turn every 16 hours or so.
I apologize for asking you to interpret my shorthand.