PDF Annotator will be installed on any of my laptops since I started inking on my Lenovo Windows tablet roughly 9 years ago. Grahl software’s flagship is an amazing tool to annotate PDF-files, for example freehand pen comments, highlight like a text-marker, stamps, typed comments etc.
PDF Annotator has 320.000+ happy users in 89 countries since 2004. I started using 1.5 when it was released back in 2007, while the latest version is PDF Annotator 6.