Oooh, interesting question, punkfolkrocker. My Google Search turned up all sorts of interesting ideas. I happen to have an old Fire I can try to hack...

My Galaxy Tab A arrived yesterday. Took a while to download apps, but it's working very well. And it's very fast. It's more-or-less like a Samsung Galaxy phone, with a 10-inch screen, that doesn't make calls. Everything about it works well.

Since this tablet uses WiFi, I wondered how I can access maps when I'm out of WiFi range. For that matter, I really needed a map on my cell phone when I was lost in the wilderness south of Mount Rainier last month and out of cell phone range. So, Google Maps tells me I can save a map before going into the wilderness, and then I'll be all set. Here's how (click). The general idea is that you view the map ahead of time when you're someplace safe and warm, and then you go to the menu and choose "save offline map."
-Joe-