iBooks is a built-in app for iOS devices that enables the user to read and download books and audiobooks from every possible category. It features new releases, curated collections, and exclusive content all directed in a user-friendly interface.
Open Library is an initiative of the Internet Archive, a non-profit, building a digital library of Internet sites and other cultural artifacts in digital form. The site has more than 1 million free ebooks.
Many Books is a website where users can download over thousands of e-books for free. They have a huge collection of romance books. mystery and thriller books. science fiction, action and adventure, and many more.
Feedbooks is a website which features books in various genres such as romance, juvenile, young adult, thriller, fantasy, erotica, action, Christian, etc. Their website also features ebooks which can be read for free.
eReader Prestigio is an app to read and listen to texts and books. It has material for kids and adults, it has more than 50,000 texts and books. Moreover, if you are a noctural reader, there is night mode.