Thanks for your comments!
The fact that the numbers are difficult to read is totally true and we are aware of it. We tried to make them white but we had problems with the paint wearing off too fast, so we decided to leave them “naked” at least for the first lot.
Part of the “alpha” purpose is for us to learn how to produce beautiful and 100% functional cards so we’re already learning and thinking on improvements thanks to this amazing kind of messages. We’ll keep in mind your protanopia and doublecheck with you the next card designs if you don’t mind.
Let me ask you about the app. Any difficult contrast or confusing colour so far? (We check every screen with colour-blind testing software to ensure proper contrast but it’s always better to check with real users 
Thanks!!