Freda can get books from on-line catalogs like Feedbooks, Smashwords and the Gutenberg Project. Or if you have an existing book collection, you can use OneDrive, DropBox or Calibre to share it with your phone. Freda can also download books from any website and from email attachments.
You can download books and keep them on your phone, so you can carry on reading when you don't have network connectivity, and you can pin your favourite books to the Start page.
Freda is a free, advertising-supported app, displaying advertising at the bottom of its main page. If you don't want to see advertising, there is an in-app purchase option to remove it).
The manual is at http://www.turnipsoft.co.uk/freda .