Android users have been begging Google to add a dark theme, or mode, to the mobile platform for years. With Android Oreo, Google added a dark mode that activated based on the wallpaper you were using. Google then removed the feature, saying it was accidentally released. Starting with not only is dark mode back but now there's a manual way to switch to it on demand.
Outside of looks, why would you want to use a dark mode on your Android device? According to Google,It turns out, all of that empty white space that Google (and Apple) has been using over the past few years uses more power, which in turn drains your battery. A darker interface requires less power and is less taxing on your battery.
To switch to dark mode in Android Pie, open the Settings app and select Display. Next, tap Advanced and scroll down until you find Device theme; tap it, followed by Dark.
That's all there is to it. Now when you view your app drawer or the quick-settings card (swipe down from the top of the screen), it'll be in dark mode.
Originally published July 19.
Update, Nov. 9: Added details about saving battery life.
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