Amit Agarwal from Digital Inspiration made a great job to bring the sizes of major e-bookstores to a comparable level. He used Google search to find the number of books in Amazon’s Kindle Store, Sony eBookStore, Barnes&Noble and iBookstore.
It’s obvious that the official numbers are overstated as they include free books from Google Books or Project Gutenberg. When you count them out, the results are shocking. According to Digital Inspiration the sizes are:
Kindle Store: 691 937
Sony eBookStore: 58 800
Barnes&Noble: 25 500
iBookstore: 22 400
Read a whole article here.
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