Secret Master - Sign Docs Protect Files keeps your documents safe. It allows you to add and store PDF documents in one place. There are two different modes of editing: work with texts or their annotations. You can add categories and sort your documents by name, size, date, and author. You may add nice signatures and edit them by changing the line thickness, color, and size. Underline, strikethrough the text, highlight it and add different stamps and graphical primitives such as square, circle, triangle to your PDF document and change their colors. In order to be sure that no one else will have access to the documents with your signature, and for copy and print protection, there is the ability to set a password.