PDF markup app for Windows. Used to be $17 I think. The price varies all the time.
From the store description-
Drawboard PDF is renowned for smooth and natural pen inking, uniquely intuitive and easy user interface, pen and touch compatibility and an impressive array of markup and text review tools. And of course, all our annotations comply with global PDF specification standards.
They also have some sort of pro subscription which is paid but optional. The base app has all the features most people need.