The currency are Galleons at Alohomora. They are titled with an G or as an image
. You can earn Galleons when you play games, donate something or master a deck. You can buy different packages at the Diagon Alley.
At the Diagon Alley, you can buy different packages of cards like random cards or choice cards. You can earn coupons at some game and you have to change it in the shop.