This post helps to add a text box to PDF using a free software and an online tool. You can adjust the size of text box, text style, etc.

In other words, Adobe Reader won't let you add text. What you need is a program that's a little more accommodating, PDF-wise. Try Foxit Reader 4.3, which allows you to add text to any PDF.

Need to edit a PDF document but don’t want to pay for the more expensive Adobe editors? You can add text to and sign a PDF with just the free Reader program.

Quick tip: You can also sign a PDF document on any device, without the need for a printer or scanner. Here's how to type on a PDF, whether you're using a Mac, PC, mobile device, or Microsoft Word.

This version allows you to add text and signatures, draw on it, and check boxes. All you need to do is open a PDF file in the new Firefox and use the markup options in the upper right-hand corner ...