Sometimes you may want to use a card again either in the same board or a new board that you are working on.  The fastest way to accomplish this is by just copying and pasting the individual card.

How is this done?  Very simple.  On the edit boards screen just double tap on the thumbnail that you want to copy and you will see a menu appear. (see screenshot below).

Now press on copy to copy the card.  Next, go to the board / the place in the board where you want to add the card.  This time, double tap on the card / spot where you want to insert the card you just copied.  You will see the menu appear with two options (copy or paste).  Select paste to insert the card or select copy to copy the new card that you just pressed on.  Voila!  You are all set.