OLED screen panels can display black pixels with almost no energy cost. So it follows that using apps with more black would save your phone battery.
Google agrees, and it’s designing more of its Android apps with a dark theme.
The company said as much at its Android Developer Summit in Mountain View yesterday,
showing dramatic power saving when using Dark Mode in its official apps on an OLED screen.
At 50% brightness,
the new Dark Mode interface in the YouTube app saves a little under 15% screen energy when using blacks and muted grays over a flat white background.
At 100% screen brightness,
the dark interface is saving a whopping 60% of screen energy.
You can see the technical breakdown from the developer conference in the video below.
Battery-saving black interfaces have been known about for years—it’s what enables always-on ambient displays, as first seen on the Moto X and then adopted by Google, Samsung, and others. This trick doesn’t apply to LCD screens, as used in some budget designs (including most inexpensive Android phones and the iPhone XR). But on the basis that a huge percentage of users will see a considerable battery boost from darker apps, and even those who won’t might appreciate the rest for their eyes, Google is pushing for more Dark Mode options in its own apps and encouraging developers to do the same.
While Google’s default color scheme has used white as a base since its Material Design overhaul several years ago, it looks like the company is planning on releasing more apps with a Dark Mode option like YouTube and the default Android phone app. The latest Android OS release, Pie, includes a system-wide dark mode option: enable it by going to Display Settings and tapping “Device Theme.”