The word card has three boxes (tabs). Swiping left moves the word card to the left box, and swiping right moves it to the right box. When swiping, the "answer" will be visible behind the card for a certain period of time. Swipe quickly and memorize words repeatedly.

You can use boxes in any way you like. You can use the right side of the box for words you have memorized, the left side for words you have not memorized, etc.
You can also delete word cards by each box.

Word cards are created by handwritten notes. Write in the 'Question' and 'Answer' areas respectively.
Use the other areas for notes and practice.
If the screen is too small to write on, try pinching in to zoom in or turning the screen sideways.

The cover of the word card should be handwritten in the same way.