Where you can create a new flashcard note. So one page of that note has a back and front (double tap to flip?). You can handwrite, insert images, type, or do anything can normally do on a note. There's also an option to shuffle your flashcard note, and an option to view your deck from front first or back first.
A blackout function
A hide/reveal function where you can black out certain parts of your notes temporarily for recall. (Double click to reveal the blacked out text. 'Turn on blackout mode' - this mode stays on until you turn it off i.e. doesn't revert back to normal when you close the app. When you turn off the mode the blackouts that you made are saved for when you turn it back on.
And how cool would it be if you could combine these two features. I hope that made sense lol.