GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
boook.link - boook.link is a web-based tool for creating one single link / landing page for a book, so your readers can choose from which store to buy the book.
Goodreads - See what your friends are reading.
Mockupea - Mockupea is an online tool for creating 3d book mockups with a lot of features.
Read This Twice - Verified book recommendations from people we look up to
Papermine - Create stunning digital booklets.