Transferrng files between Kindle Paperwhite and an SD card
I am looking for a way to transfer ebooks between a Kindle Paperwhite and an SD card, using USB cables and a minimum of other hardware. My library is expected to run to about 4000 books, and I want them all local. The linking hardware must be powered by rechargeable batteries, but it should be less power-hungry than a laptop. (I'll buy a laptop to solve this problem, if necessary, but there ought to be a battery-operated device that will do these transfers with a lower power requirement.) The best solution would be for Amazon to create and sell its own brand of expanded storage media for the Kindle Paperwhite. I'd buy one. I don't want to jailbreak my Kindle, but I will if I have to, in order to get the ability to increase the storage with SD cards.