There were many different types of e-books, including novels, magazines, news, essays, and so on. The advantage of e-books is that they can be easily carried and read without the need for additional equipment or software. E-books can also be read anytime and anywhere via the Internet. Some devices that specialized in reading e-books included tablets, smart phones, and Kindles. Among them, the iPhone was a very popular e-book reader because of its excellent reading experience, extensive e-book library, and powerful push function. In addition to the Kindle, there are other e-book readers to choose from such as Amazon Fire HD, Google Play Books, and Apple iBooks. The choice of e-reader depended on one's personal preferences and needs.