Last Card Wizard app for iPhone and iPad

The Last Card Wizard is based on a magic card trick. There is a magician (or wizard) and a player. The player chooses a secret number between one and ten. The wizard supplies a well-shuffled deck of playing cards. The play counts through the deal according to simple rules and when they reach the end of the deck, the wizard tells them what their last card was, before running off the end of the deck.

In this app the player watches the cards get shuffled and then taps every card without revealing what their secret number was. When the player reaches the end of the deal the app announces the name of the last card in the player sequence and highlights that card in yellow.

The original "last card" card trick was invented by the late mathematician Martin D. Kruskal (1925 - 2006) of Princeton University. It was popularized by Martin Gardener in his Scientific American column, Mathematical Recreations. The is a formal mathematical paper titled The Kruskal Count; it explains why the magician will identify the last card in the sequence about 85% of the time. The wizard in this app identifies it correctly 100% of the time.

The card trick was performed on the Johnny Carsons Tonight Show around 1975.

The player of this app can shuffle and re-shuffle the deck over and over again, choose whatever numbers between one and ten, and the wizard will correctly identify their last card 100% of the time.