The 2.0.4 version of TagNotate for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this software for Mac is Tim and Gerry Inc. The program lies within Productivity Tools, more precisely Office Tools. We recommend checking the downloaded files with any free antivirus.
From the developer:
TagNotate is a PDF viewer and annotator with the unique ability to assign tags to annotations - you can create as many different tags as you want, allowing you to associate with each annotation whatever kinds of information are important for you.
You may want to check out more software for Mac, such as Apimac Clean Text, TAMSAnalyzer or Gordon, which might be similar to TagNotate.