I was just thinking about the impact iOS 11 will have going forward. Right now with iOS 10 and earlier, all the image and video output of the various iPhones is handled quite well by pretty much all recent iMacs. In fact, the 4K 2160p30 video that is output by my iPhone 7 Plus plays and scrubs just fine even on my ancient 2010 Core i7 870, without significant fan noise. However, the switch will be flicked when iOS 11 launches. All of a sudden, there will be a bazillion people out there recording h.265 HEVC 4K video with their iPhones. This will wreak havoc with people with older iMacs, which is a lot of people, since it seems to me people replace their iPhones a lot sooner than they replace their desktops (or laptops). Yes, you can turn off the HEVC encoding feature, but once it's there, it will change the way people look at their computers. It's also a very nice feature to have active on an iPhone, since it saves about 30% to 50% of storage space.