[Heron_Kusanagi]

I have no clue how possible this is, but given that they created a camera grip from Nokia, why can't they create a 'Camera Grip Pro' with a zoom lens?

[Laura Knotek]

I think it would be possible. However, I don't think it would be a good seller. Most people who are interested in DSLRs (and the interchangeable lenses) tend to be photographers (pro or amateur), not general consumers. The photographers will already use Nikon, Canon, etc, DSLRs and high-end lenses (Nikkor, Canon, Tamron, etc) not phones.