Bill, work in Android. iPhone is so very last year. There are online resources and GPS functions that permit all sorts of fun with phones these days. The very first or most obvious of which is using your phone to get Tommy Wonder's "Tamed Card" routine started when you want.
Using a PK ring gaff to cue a phone is no biggie. Perhaps using that to invert an image to a left handed card after a top change might amuse. ;)
Mundus vult decipi -per Caleb Carr's story Killing Time