Certain types of modern monitors use less power when displaying a black or dark background, including the technology used in the Apple Watch. It̵
Why do dark themes use less power?
From the very first model, Apple chose OLED display technology for the Apple Watch. Unlike traditional LED-lit LCD screens, OLED is a self-emitting technology. That means that no backlighting is required at all, as each pixel generates its own light.
This provides pixel-level light control and perfect black tones. To display pure black, pixels are simply turned off. This does not consume any power and ensures that the rest of the dial stands out against the deep black background.
Dials that mainly use dark or black elements consume less power than a dial with many bright white or colorful elements. The brighter a pixel, the more power it consumes. If you can replace a bright solid background with a black one, the display will use less power because more pixels are turned off.
It’s hard to tell How much this affects your battery usage so the best way to find out is to try it yourself. If your Apple Watch’s battery is often low, a dark background can make a small difference. It’s worth the try. If you have solid battery life, you may not notice the difference.
Normal LCD backlit screens do not turn off the backlight when displaying black or dark colors. Instead, they ‘block’ the backlight with varying degrees of success. Not only does this require the use of an always-on backlight, but it also makes black look washed out.
Some iPhones can also take advantage of this
It’s not just your Apple Watch that can see a battery boost that the self-emitting display technology brings. Some of the more expensive iPhones in recent years also have OLED screens.
If you have an iPhone X, iPhone XS or XS Max, iPhone 11 Pro or Pro Max, or an iPhone 12 model (Pro or otherwise), your device uses an OLED screen. If you want to get a little more battery life out of your iPhone, you may want to set a dark wallpaper and enable dark mode.
RELATED: 8 tips to extend the battery life on your iPhone
Try switching to a dark background today
If you’re experiencing less than ideal battery life on your Apple Watch, a dark background can help, especially if you have an Apple Watch with an always-on screen, such as a Series 5 or Series 6.
Learn how to change your watch face or install someone else’s Apple Watch face.
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