1, Expert PDF Reader is a completely free PDF reader, which can be used to read and print PDF files. Functionally, it supports editing and modifying documents, such as inserting watermarks and adding various comments. Generally speaking, EXPert is relatively simple, the software startup speed is quite fast, and the overall interface is simple. The operation of browsing documents is also suitable for users, and it is more suitable for users who only need to read simply.

2.goodreader is also a good reading software, which supports browsing Office documents, PDF, TXT, HTML and other files, playing video and audio (media format supported by iPhone), supporting horizontal screen, and sharing files with PC or MAC*** via WI-FI.

3.iBooks As the official e-book reader application launched by Apple, iBooks has inherited Apple's consistent good experience. The reading mode of iBooks is also very user-friendly and can be adjusted according to your personal habits. You can browse the whole page in vertical screen mode. If you are not used to this mode, you can also read files in landscape mode. Similarly, you can change the font size or font type, click a word or word with your finger, you can enable Wikipedia or a built-in dictionary to find relevant information, or search relevant information online.