@onutz

IMHO your stated reasons are really far fetched. A ton of existing iPhone applications are just frontends to different web services and the developers do make money, so why would a frontend to a porn service not serve the same purpose? Financially it would make no difference to Apple whether the money comes from a porn app or a productivity app, except porn apps would probably sell more.

It's a brand issue. The impression I have is that in the US holds quite a double standard when it comes to porn. They produce an insane amount of it yearly, but it's still somewhat of a taboo in the collective publics eye. Apple wants to avoid scandalous headlines that could smear the polished brand.