Learning square dance calls can be difficult! Lots of calls with similar names, similar actions, and as you go up in levels there are hundreds! And we need the exact definition in order to use the parts or dance phantom. It's natural to think of flashcards to help retain the material.
I strongly recommend utilizing spaced repetition systems (SRS) rather than a generic flashcard app like Evernote (or physical cards). I recommend Anki as the most comprehensive, flexible, and well-supported app. You can find a basic "how to install Anki and get decks" here.
Noriko Takahashi and I created the first deck of C4 calls, when you do "get shared deck" search for "C4Flashcards".
Ben Rubright and I updated his long-standing set of C3B definitions, when you do "get shared deck" search for "C3BFlashcards".