Inspired by the YouTube video "The Pigeon Hole Principle: 7 gorgeous proofs" by Burkard Polster (Mathologer): https://www.youtube.com/watch?v=TCZ3YwbcDaw
Explaining PDF: https://web.northeastern.edu/seigen/11Magic/FitchCheneyFiveCardCount/Fitch%20Cheney%27s%20Five%20Card%20Trick%20-%20Colm%20Mulcahy.pdf
How to use
The order of the cards for the ranking is 2, 3, 4, ... A and diamonds, hearts, spades, clubs.
In the iOS Settings app, you can scroll to Fitch Cheney and adjust (a) the language of the only word (card) and the position of the key card between 1 and 4