https://www.bleepingcomputer.com/news/microsoft/microsoft-is-updating-windows-10-mail-app-with-new-features-for-insiders/

Microsoft recently released a new update for the default Windows 10 Mail app to Windows Insiders that brings a few new touch related features such as a Drawing Canvas, the ability annotate pictures, and new ink effects.

The most interesting feature is the Drawing Canvas, which allows users to insert an area into an email where they can draw, sketch, and doodle a picture and send it to a recipient. This feature supports both using a pen or selecting "Draw with Touch" in order to use your fingers.