My Kindle is back lit. It reads best in the dark and I do not need reading glasses. Yes you are right I read lying on my side with my head on the pillow and my Kindle held flat against the mattress.
For serious bedtime reading I sit up and read a book, but for those last few minutes as I drift asleep or if I wake in the night and do not want to wake too much, I just slide my Kindle out from under the pillow, switch it on, I have the light and colour as low as possible for practical reading and most of the bookson it are well read favourites, so I just drift off to sleep as I read.