The way I perform the effect. If the spectator is paying attention at all will and does notice the difference in the app screen and the normal screen of the phone. What I am referring to is the difference in the four bottom buttons, ios3.x has a white crosshatch pattern behind them, ios4.x. Has a three dimensional look like the buttons are sitting on.
Enjoy! We have many more ideas on this for the future, but the v2 update represents a quantum leap from the original version. New graphics, new features, and better instruction (for people that are downloading it for the first time). Whenever iOS4 technology catches up to the point where we can allow you to choose which deck you'd like to use, we will enable that feature. It was originally scheduled to be in this v2 launch, but adding it in required significant load time when opening the app, so we shelved that idea until we can do so without affecting launch time.
I have an iPhone 4. No it's not jailbroken and it's never launched properly. Everytime I tap the app, a hand with a deck of cards flashes on screen then it returns to my home screen.