Do I really need... higher resolution?

What does it do?

The higher the resolution of a screen, the more pixels it contains, and the more detail it can show you. Comparing screens that are the same physical size, the one with higher resolution (A) has smaller pixels packed closer together, giving higher ‘pixel density’ than (B).

Why would I want it?

More pixels means you can see more stuff at once, which is why the typical PC screen grew from 7-10in to 2327in. But we don’t want phones and tablets to keep getting bigger, so manufacturers are miniaturising LCD cells further to pack more detail in.

What’s the catch?

Beyond a certain point, you can’t see any more detail within a given space using human eyes. That point was arguably reached in 2010, with the iphone 4’s Retina display. Yet screens have continued to gain pixel density way beyond Retina’s 326 pixels per inch (ppi). Sony’s Xperia XZ Premium phone (see our review, Issue 508) has more than 800ppi.

So can I do without it?

Unless you’re bionic, your eyes can’t tell the difference between, say, 500 and 600ppi. So science tells us you can’t possibly need 800. But smartphones can now be used as displays for virtual-reality apps (see Issue 490, page 22), which creates a real need for more resolution by depicting a wider field of view, making each pixel bigger to your eye.

For everyday tasks, high resolution is more than a gimmick. A sharper screen makes text clearer and more comfortable to read. Combined with high-dynamic range, high density also makes photos, videos and games feel more real.