The new dark mode feature introduced with the iPhone 11 series phones on iOS 13 looks great. On OLED iPhone displays, there is excellent contrast because of the true blacks that OLED can display. There is another major advantage to dark mode, though. This is in terms of iPhone battery life.
Yes, enabling dark mode can by itself significantly boost your iPhone’s battery life. This arguably makes it as important a battery tweak as the settings in iOS 13’s battery settings panel. But exactly how much better can your battery life get with dark mode enabled? The folks over at PhoneBuff went ahead and did a test with robotic arms to find out. They used two previous-gen iPhone XSs as their test platforms.
Dark Mode Test Sees Battery Life Extended by 30 Percent
They ran the XSs through a range of apps that feature both dark mode and the standard light mode. This included running Messages, using Google Maps, watching Youtube, and other tasks. They essentially replicated a set of real-world use cases. The only difference was that one phone was running dark mode and the other wasn’t.
What were their findings? Remarkably, using dark mode could extend your battery life by as much as 30 percent. By the seven and a half hour mark in their test, the light mode XS ran out of battery. The one under dark mode still had 30 percent juice left. However, at all times, the dark mode device had more battery in the tank, though the gap widened as the overall battery percentage fell.
What is the likely reason for such a large difference in battery life just by enabling this one setting? It has to do with how OLED displays work. Unlike LCD displays, OLED displays don’t have a backlight. Instead, tiny LEDs are individually turned on and off to light up pixels. This means that “true black” is possible. On LCD displays, black only shows up as a dark grey since the backlight still has to be on.
On an OLED panel, parts of the screen that are to be black simply don’t light up. Not lighting up obviously means that these LEDs aren’t consuming power. When you’re using a dark theme, a very large chunk of pixels on the display won’t be turned on at any given point of time, bringing the display’s consumption down significantly.
It must be mentioned here, though, that dark mode only noticeably enhances battery life on iPhones with OLED displays. This means that iPhone X, XS series, and 11 Pro series users will gain the most benefit. While dark mode still uses less power on the XR, 11, and older iPhones, there are other effective ways that you can reduce battery consumption there.