I've never had a Kindle, but I do use the Kindle app. I have a (discontinued) Samsung Galaxy Player with WiFi that runs android Gingerbread, so I bring books and all the guides you mentioned, but It also has full GPS, so I have The MapsWithMe app downloaded, as well as the Navionics lake app. The map app has many trails on it as well. Not that I'd trust it with my life, but it's plenty accurate enough to at least know the right direction when using a compass. I actually strap it to my handlebars when riding on the roads going bike-camping and plug it into my GoalZero solar panel on the back rack and wander back roads to my destination! (full time GPS is a bit of a battery hog)
Then it has an FM receiver built in, so I can get radio for weather or news. I'm not a great photographer, so the camera on it is good enough for me. A couple of simple games, a few movies (32g sd card) and lots of mp3's of course (need audiobooks). Then I have photo's loaded of all my important documents, licenses, savers/membership cards, etc. People think I'm a bit off (maybe I am lol) when they see a photo of my DL as my lock screen image. Hey, I solo all I do, never know... My "phone" (looks like a smartphone) might be all an EMT or SAR finds left of me!
But the most important thing I have on it is the ThinkFree app that runs the excel spreadsheet of all my gear weights! Nothing like crunching UL numbers while in the field :-) There's also the note app, for jotting ideas, or the voice recorder if I'm feeling especially inspired that day.
Device, headphones and an extra battery all come in at 5.4 ounces.
Oh, this is my first post here at BPL, so sorry if I'm a bit longwinded. Hopefully you'll get used to it lol