I like it because it's straight forward. Good stuff!
It's not fishy like a number of smart phone "magic tricks" seem to be.
Of course, I'd rather do the classic effect with an actual deck of cards, but having this ready on a phone is smart since with me even at work my phone is glued to me whereas if I'm not at my desk then I'm not at my deck. ;-)
Note that your technique (under my
assumption of what your technique is) is not iPhone-exclusive.
In the default "Gallery" app on Droids, you can play a video and when it finishes it holds on the last frame. You can then swipe over to the next/previous image/video file just as cleanly.
With Android v4.0 and later, you can take a screenshot by holding the Power button and the Volume Down button.
Just some useful information in case you have ambition to make a video for release on The Wire or such -- just grab a friend with a modern Droid phone and show it with that as well. =)