Readwise - Effortlessly rediscover and organize your Kindle highlights
GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
Clippings.io - Organize the notes you make on your Kindle
Goodreads - See what your friends are reading.
Klib - Kindle & iBooks Highlights Manager
Bookicious - Find the best new book to read with books collections for makers, founders and entrepreneurs.