I enthusiastically recommend a Kindle Paperwhite. My steps that led to this purchase:

- bought a Nook. Felt economic book deals were rarer than with Amazon. Returned it.
- bought a Kindle
- shortly thereafter, bought a Kindle Paperwhite. And now I am content. I like it because I can read in a dark room or on a plane even if the lightbulb is burned out.

I signed up for bookbub.com. Everyday, I get an email with books that fit my profile, ranging from free up to $3.