Hello, I've been using my iPhone 6s+ since launch day after upgrading from the 5s. I notice that, on occasion, the graphics on the screen float down to about the half way point. IE the top 50% of the screen becomes blank, and the safari window i have open occupies the bottom 50%. The graphical transition to this state is quite smooth, so I assume it's a feature and not a bug. But I can't figure out how to activate/de-activate the feature, after trying dozens of different 3d touch/touch gestures, sound motion etc. Does anybody know what this feature is called? How to initiate the feature? Thanks, much appreciated.