Some people claim that paper books are better than e-readers. However, the electronic devices have advantages which make them indispensable.
First of all, e-books can be read anywhere, as e-readers are mobile, and because a user can have virtually the whole library in a single device. In comparison with other gadgets, it has longer battery life and there is no damage to the eyes, because the electronic paper technology allows the screen reflect light like ordinary paper without the need for a backlight. Moreover, in the latest models, notes can be made and it is very convenient for work and study.
In addition, the devices are economical. Electronic books are cheaper than their printed versions. Besides, many of them may be downloaded for free.
To sum up, I consider e-readers an irreplaceable invention that makes reading more accessible and convenient.