GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
Booknshelf - Social book and bookshelf discovery platform.
Oku - Track your book lists and get recs from your friends
Readminder for iOS - Track your reading record and keep your favorite quotes
Bookicious - Find the best new book to read with books collections for makers, founders and entrepreneurs.
Kooba - An interactive graph for finding new books