The Xperia Z5 Premium UI uses 1080p, not 4K resolution; Sony answers
In our coverage of the Xperia Z5 Premium, we pointed out that Sony’s “Premium” phone has a 4K resolution of 3,840 x 2,160p (or 4K Ultra HD), for a total of 8 million+ pixels that have been crammed into the display. The same day in which Sony announced the new phone, Sony also announced that the smartphone had a massive, 3,430mAh battery and the Japanese manufacturer continued to affirm that the Xperia Z5 Premium, as all of Sony’s Xperia Z smartphones, would have a two-day battery life. It seemed unbelievable at the time, but we now know how Sony can achieve this – and the answer is not complicated at all.
Sony UK has issued a statement on how the company can provide 2-day battery life for Xperia Z5 Premium users:
Xperia Z5 Premium features a 4K display with a resolution of 3840 x 2160 pixels based on SID standard and enables all video and image content to be enjoyed in 4K resolution. All other content is displayed at 1080p or lower resolution in order to optimise the performance and battery stamina for the device, ensuring you can enjoy the 4K resolution when you need it most.
What can be gathered from Sony’s statement? In short, only the gallery and video player provide 4K resolution content; the rest of the web browsing experience, including the main screen (user interface, or UI), games, and web pages are rendered in 1080p (Full HD) or lower. In short, this means that you won’t get to enjoy 4K resolution all the time, and Sony’s reason for limiting the 4K resolution has to do with battery life.
At the same time, however, this makes the Xperia Z5 Premium’s 4K resolution nothing more than a gimmick. Who wants to own a device with that kind of resolution, only to have the company choose to limit how and when I can access it? Many tech reviewers have compared the Z5 Premium to Samsung’s Galaxy S6 and S6 edge, which has 577ppi and a Quad HD resolution, but you can’t put those in the same circle. After all, Samsung’s devices allow you to experience Quad HD resolution all the time, as opposed to only the image gallery and video player of the Xperia Z5 Premium. It’s the equivalent of a race car driver only being able to drive 100mph “only when the gas tank is full,” meaning that, most of the time, his car’s fastest speed would be unavailable and inaccessible. What’s the purpose of having it in the first place if the majority of my web browsing experience runs on 1080p or lower?
There is another side to consider with the Z5 Premium, however: that is, that some will welcome Sony’s decision. These users don’t care for 4K resolution and would rather have excellent battery life than a battery-guzzling resolution. At the same time, Sony could allow some to maintain their 4K resolution regardless, but we have a feeling that the Snapdragon 810 processor would ruin the experience and lead to app crashing and overheating if Sony complied with this request.
In the end, Sony hasn’t figured out a way to improve its battery life, meaning that the Xperia Z5 Premium’s 4K resolution is something of a marketing gimmick. We’re not one to call higher-resolution screens “gimmicks,” but it is when you limit the resolution you claim lies in the smartphone while still saying that your smartphone is “the world’s first 4K smartphone.”