The reason why e-books are so expensive is because they cost a lot. Its high cost is high in its display, an e-book display cost to account for 40% -60% of the total cost.

The e-reader's display is made of electronic ink, which can only display black and white colors. Its advantage is that it does not hurt the eyes, power saving, but the disadvantage is that the cost is very high, the technical difficulty. The current technology is not good enough to bring down its cost, so the real electric paper book are more expensive.