How the creator of a PDF file sets up her document determines the extent to which you can use Acrobat Reader's commenting tools to mark the file with notes about its content.

How to add text to a PDF on a Mac, modify a PDF Once you have the PDF document open in Preview (or Quick Look), try clicking in the space where the PDF indicates you should enter some data.

This article show three methods that can be used to add audio comments to PDF documents in Adobe Acrobat free and Pro version.

If you're looking for a quick way to edit or sign a PDF document, there are free and easy-to-use tools for iOS, Windows, and Android devices.

Just like how you add inked signatures on a hard-paper document, you can also add an electronic signature to your PDF document in the Edge browser.

How to Sign a PDF Document on Android Unlike an iPhone or iPad, the default file manager that comes pre-installed with most Android skins doesn’t offer a built-in PDF signing feature.

How to navigate a PDF document using Microsoft Edge On the Windows 10 Fall Creators Update, Microsoft Edge is getting a lot of PDF improvements, some of which you'll notice immediately in the toolbar.