Amaze your friends with your ability to read the future. The iPhone will shuffle in front of your friend a deck of cards. Ask your friend, at any time she likes and at her own free will to touch the screen and not to wait for any specific card. To her surprise, the last card to be shuffled will be known in advance to you.Try to use the following additional steps: place a real card in a sealed envelope. Once the card shuffling has stopped, by your friend, ask her to reveal the sealed card.If your friend is suspicious, you can allow her to play with the shuffling and selection as much as she likes. You only need to observe what was the result of her last selection and then, using a simple formula you can run in your head, you will be able to determine what will be her next selection (of course using the envelop trick will have to be modified accordingly.)The suit and rank of the card to be selected by your friend is set in the applications page found at the bottom of theSettings application of the iPhone/iPod Touch. Following selections are advanced according to a simple formula described on the page. However, if you want, you can disable this pseudorandom advance, and the same card will appear at every selection. In addition you can control the speed in which the cards are shuffled. This is crucial for generating a good magic effect. Too fast, and your friend will not have the feeling that she made the selection, but too slow will make the trick obvious.Many thanks for all the users of this application that sent constructive comments. I want to give special thanks to Lukas Olson and Raymond Leong.