Neat! I though I saw something like that 'holographic' app some time ago, even seem to remember that 'cat.'
Still, the 'virtual' pet app was very interesting, especially with the interaction of the 'targets.' Lots of potential there for some crazy interactions with different kids of objects by different kinds of animals! How about a target that already looks like a food bowl, water dish, a moving rabbit, a pet bed, etc.?! Just the use of the cpu/app to recognize objects makes all kinds of apps possible!
Hold the iPhone above your head and search for that too-exuberant child that won't stay next to you...where is my friend in this crowd...where did I park my car...