While e-books offer practicality, convenience, the ability to store hundreds of books on a single device, an abundance of features such as a light and dictionary. (hubpages.com)
The service itself is free to use on a single device, and is only $ 12 a year should you wish to take advantage of the premium subscription. (androidcentral.com)
It allows for multiple user accounts on a single device, as well as custom notifications for specific contacts. (dzgn.co)