on Just Publishing Advice:
Kindle Create helps you format your Kindle ebook
If you are self-publishing on Amazon Kindle Direct Publishing (KDP), this is a must-have free app for you to use.
The program has improved considerably over the last couple of years. Initially, it was a little unstable and its basic function was to help you format a Kindle book.
But stability is much better now and Amazon has been slowly adding new features since it merged Createspace into KDP. While still in beta, Kindle Create can now format paperback books as well.