I really think you should start paying more attention to how your theme works on Apple mobile devices. They represent a large part of mobile users, and every webmaster knows those users are also the paying ones!
As of now, after 1.2 update, the portfolio gallery is UNUSABLE on all iphones (tested on 4s, 5s, 6 and 6plus), and ipads too (tested on Retina iPad). The gallery in your DEMO theme works fine, due to the fact that it contains very few low-res images. If you create a real-world gallery of 30-50 images, it crashes IOS Safari very often. Especially bad is auto-change of orientation (from portrait to landscape and vice versa), and also just moving from one image to the other in full screen viewing mode. You can use my gallery to replicate this: http://shumsky.info/?portfolio=ios-bug-test
You told me the theme developers do not have any iphones and consequently do not test the theme for issues on apple devices. This is totally wrong attitude, and I suggest that you please, please think about it.