The rise of dark mode in UI design

Dark mode or light mode, which are you?

I’m a strictly dark mode user. Practically everything I use day-to-day comes with dark mode: from my phone to Slack. Even the NHS Test & Trace app has one. I can’t explain why, but dark mode is just better (sorry light moders, you’re wrong).

There are a few who continue to resist the rise of dark mode. Most Google products don’t have the option for one, although that looks set to change soon (which is a relief – I once tried a browser plugin to invert the colours of Google Docs, but it didn’t look right).

Where did this trend come from? And, why do people feel so strongly about it?

A brief history of dark mode

Once upon a time, there was only dark mode. The earliest computer monitors, powered by cathode ray tubes (CRT), were monochromatic by default. It was not until the release of the Apple II in 1977, and then the Atari 800 in 1979, that primitive colour displays started to appear in personal computers. Even then, it was not until the late 1980s that computer interfaces began to enjoy a wide range of colours.

Strangely, while these early computers may have lacked colour, they did enjoy a technology we’re very familiar with these days: touchscreens, as seen with the Fairlight CMI released in 1979.

We’d stick with these CRTs through to the mid-noughties, when LCD ushered in a revolution in the way we designed computers. Seemingly overnight big, boxy CRTs were replaced by elegant LCD flat screens. You can actually see this transition with Apple’s iMac. While the original CRT-based model is regarded as an icon of industrial design, the iMac G4 – released only 4 years later – took Apple in a radical new direction not too dissimilar from where they are today.



This eventually led the way to the LED and OLED screens we use today that generate a wide spectrum of colours that earlier product designers could only dream of. OLED screens are the real innovation here: each pixel in an OLED screen emits its own light and can be turned on or off individually, whereas LCD screens rely on backlights which makes dark areas of the screen appear ‘grey’ rather than black. OLED screens not only provide a true black backdrop for any image (perfect for that sleek dark mode UI), but they’re also the only kind of display that conserves power in dark mode.

Dark mode evangelism

Dark moders are proselytizing the cause across the internet by touting a range of benefits: longer battery life, improved legibility and reduced eye strain. But, are any of those actually true? In terms of battery life, you’ll need an OLED screen to see any benefits. And when it comes to legibility and eye strain, anyone who has sat through a class on the fundamentals of graphic design has had it hammered into them that black text on a white background is the ideal in legibility – there’s a reason you’ve never read a novel with white text on black paper.

However, there are exceptions. Many code editors, from Vim to VS Code, default to dark mode. Code is, by definition, visually complex. By using dark mode, these editors help you focus on individual parts of a screen, providing somewhat of a visual respite from overstimulation. Colours, which stand out against the contrast, break up complex blocks of code into something that is easier to scan.

But, not everyone sticks with the default themes – there is a significant minority of developers who prefer working with lighter themes.

A matter of personal preference

At the end of the day it all comes down to personal preference. The reason I use dark mode isn’t because I care about my eyesight or battery life, it’s an aesthetic preference – I just like the way it looks. With the release of iOS 14, Apple, a company who traditionally controlled their product’s design with an iron fist, opened the doors for users to add custom icons and home screen widgets. Maybe one day soon, instead of choosing between light or dark mode – we’ll be able to create whatever theme we like.