1 over 2 million books from public domain book catalog such as Gutenberg, Feedbooks, Internet Archive, Baen Books, Smashwords.
2 you can open books in iBooks、Kindle and many other ebook reader apps you like.
3 add custom book catalog
4 search and download books from websites by the search engine you like.
All books are public domain books, so it is legal.
1 error when searching some keywords in book source Tuebl