I'm not sure if you are aware of this or not, but Microsoft has recently added OCR capabilities to Ink, so the application can now understand the things that you jot down. The company plans to put this capability to use and expand OneNote's functionality by having it automatically solve the equations that the users write in Windows Ink. This means that in the near future, Windows 10 users may no longer need to worry about their tedious (yet necessary) math homework.
Besides this upcoming Math function, OneNote will also introduce a new feature called Convert to Shapes, which will help users draw perfect geometrical shapes. All you have to do is use ink to draw your version of a circle, triangle, square, etc., then drag a lasso over your drawing to select it and use the Convert to Shapes button to have the app automatically turn your drawing into one that's geometrically sound.
Additionally, there was another really cool Ink-related feature that was supposed to come along with the Anniversary Update, but sadly Microsoft decided to delay it. The IT giant was working on a function that combined Windows Ink's capabilities with the Maps app, allowing the users to draw a route over their virtual maps. However, the company's engineers appear to have stumbled across a few obstacles, so we will have to wait a bit longer to benefit from this ability.