This is an open source hanafuda client.
Card art was designed by Louie Mantia and is used under the Creative Commons Attribution-Share Alike 4.0 International license. The cards are available on Wikimedia Commons and have only been modified to make them usable in the application, as well as to create the favicon.
Kaisei Tokumin font is created by Font-Kai and is used under the Open Font License. It is available on google and on github.