You can type on a PDF using one of several different options, depending on the device you are using.

In iOS, Apple's stock Files app is a handy place for keeping PDF documents on your iPhone or iPad. Not only can you view and organize your documents in the Files app, but it also provides you with ...

How to Darken Light PDF Files. The Adobe Reader program is a free PDF file reader that enables you to view, print and collaborate on PDF documents. If your PDF files are too light to read, use ...