Which one do you guys use?
I use a tablet with the brightness to the minimum (I read at night) with an app that allows to change even the colour of the light(Twilight is the name of the app). The eyes don't get so many light before going to sleep.
You might liek to take a look to fread.ink if you want to use something different from amazon.
Sorry for not being able to propse something more useful ;)