How to Annotate PDFs
To understand the basics of how to create, share and collaboratively annotate, itβs recommended to first check out
Annotating a URL-based PDF
To open a URL-based PDF in the annotation reader, you need to click on the Memex icon in the extension menu. Then, press the button "Open Memex PDF reader." This will open the PDF in the annotation reader, and you can start adding your annotations.
Annotating a local PDF
To open a local PDF, all you need to do is drag and drop the PDF into the dashboard. The PDF will automatically open in Reader mode, and you can start annotating it right away.

Collaboratively Annotating PDFs
Did you know that you can also collaboratively annotate PDFs, even if they are stored on your local hard drive? It doesn't matter if you move the PDF around or send it via email. If the other person opens it with Memex, it will be identified as the same one and the highlights will appear.
One way to make this a smooth experience for you and your collaborator is to have a shared Google Drive/Dropbox folder that locally replicates the PDFs. This way, everyone just has to open them on their device and start annotating right away.