If you want a simple, easy to use, free, and easy to generate PDF-ed editors, you can refer to the following: 1. Android Reader: A free, powerful, and multi-browser version of the browser, developed by Android. 2. Google Chromebrowser: The browser developed by Google has a built-in PDF-reader that is easy to use and supports a variety of PDF-format. 3. adobe InDesign: a professional publishing software developed by Adobe company. It supports the creation and editing of PDFs and is suitable for complicated publishing work. 4. MicrosoftWord: An office software developed by the company that supports the creation and editing of PDFs. It is easy to use and suitable for jobs that require simple document editing. 5. The drawing software developed by the company, which supports the creation and editing of PDF-files, is suitable for mechanical design and architectural drawing. All of the above PDF-editors are easy to use and free of charge. You can choose the right software according to your needs and habits.