A Windows personal computer is required because mobile phones, which lack keyboards and pointing devices and have small displays, are not optimal for reading scholarly English composition writings, especially "knowledge tree" writings.

There is a reason why practically every book ever printed since 1455, when the Gutenberg Bible became available, displayed text on pages significantly larger than the screens of most mobile phones in use today. Mobile phones are convenient and great for casual browsing of news and social media while riding a bus. But for the serious study of scholarly or other carefully reasoned writing, a much larger page size is optimal. This is especially true for knowledge tree writings, which require far more active reading, because the reader frequently clicks a sentence to "climb up" for more detail, and then climbs back down to continue reading at the lower level of detail.