Sony has published an extensive interview with the designers of its Xperia phones and it has some interesting tidbits. The designers are concerned with not just the "evolution" of smartphone design, but also with change. They see that smartphone design is getting stale and are keen to keep the Xperia phones fresh. The Sony Xperia XZ2 Premium is the model that lives on the cutting edge. It introduced HDR video recording to match the 4K HDR capabilities of its screen. Interestingly, the original XZ Premium also had an image sensor capable of HDR video capture, but the chipset couldn't handle...
Source: https://www.gsmarena.com/sony_xperia_designers_talk_about_camera_screen_and_thinner_bezels-news-31627.php
