IPhone 4s DSLR canon Camera adapter?

I have seen an iPhone 4 with an adapter for a Nikon DSLR.
I was wondering if there was an affordable one for the iPhone4s and a Canon DSLR?

Yes, same places and same price as the Nikon. I just wonder why.

Why would you waste your money on that in the first place? Yeah you can use a big giant lens on it but the sensor is still the size of a baby's fingernail so it makes no difference.

Of course, an adapter for canon DSLR.