Pick a number magic 1.1

the author of this app says:

Pick a Number Magic

An easy to do magic trick you can perform with your phone.

A spectator chooses a number between 1-60. A set of numbers is shown on the phone, and the spectators says if her number is visible or not. This is repeated a few more times.

When you wave your hand, the phone suddenly displays the selected number. The spectator never said what her number was, yet the number shown is the correct selection.

You can even even tell the spectator what her number was, instead of showing it on the phone.

Can be immediately repeated.

Works in any language. Instructions are in English.