iPhone USB OTG

This is complete speculation since Samsung doesn't publish the specs of the Apple branded processor, but it seems like it would at least keep some hardware compatibility to the first iPhone, which the processor for that could do USB-OTG.
I believe it is most likely that the reason it doesn't have this functionality is because of a software limitation (either by design or because of time constraints.)

My guess is that this is either a low priority, or there is some FUD (from the entertainment industry or cell carrier) that is keeping them from adding the functionality, but it may bubble up as requests for an API or the functionality increase.

The iPhone currently does not support USB on-the-go. I don't know if this is a hardware limitation or driver.

glor