I proposes a new learning support feature for the GoodNotes app, inspired by the widely used "red sheet" study method in Japan. Specifically, it replicates digitally the ability to highlight text or diagrams with a green marker and visually hide those parts for memorization purposes. This feature will allow users to efficiently memorize content they wish to learn.

Feature Details
Dedicated Marker: Users can highlight the parts they wish to memorize using a dedicated color marker (e.g., green).
Transparency Mode: Once the user exits the note's editing mode, the highlighted parts are automatically hidden.
Reveal/Hide Content: Hidden content can be temporarily revealed by tapping on the marked area. Tapping again re-hides the content.

I believe this feature come true. thank you.

(I'm not good at English, so　I'm sorry if it's difficult to read )