Played the demo for awhile, there are untranslated text in various places.
You could add own background music for different places.
Buttons could have sound effects, feels kinda empty.
In battle, you can't use card even if you can select them, they could turn red or gray if you can't use them.
Bought a sword just to notice I already had full set of armor, icon could indicate that you already have one.
Otherwise game seems pretty solid.