Have you ever thought that it is a shame that Apple forget to add a button in the Safari browser to allow people to easily upload photos from their iPhones to a website? If you build a website, and want to allow iPhone users to upload photos, the only way to do it is to hire an iPhone developer, create an iPhone app, and submit it to the AppStore. This is hands down more convoluted and troublesome than supporting development for common PC or Mac users.
Currently Collection Studio Online service doesn't support easy upload of images for iUsers. But we think that in nearest future we will add this possibility. For all other platforms upload of images works fine.