Sign PDF is a very useful tool that you can use to place your signature, watermark, or comments on the pages of a PDF quickly and easily, without having to use third-party tools. It only takes a second to sign an important document with this tool, helping you work more quickly and save lots of time with your most important documents.
To add your watermark, all you need to do is tap on the 'open document' button and find the PDF you want to edit. Once it's open, you'll have to find the page you want to work with (the trial version only lets you edit the first page) and tap on the editing option you want: add text, sign freehand, or insert an image. If you decide to sign the document, you'll have to create the signature first, which you can then insert into many other documents and save yourself a lot of time.
