For the unaware, Dark Mode is a feature that essentially flips YouTube's normal white color scheme to one mostly composed of various shades of black and gray.
To access the new theme, tap your account icon on the top right, select "Settings", then select "Dark Theme".
We spotted YouTube making progress in that direction early this year, as settings for a dark mode started to include more and more of the app's UI elements.More news: Apple's WWDC 2018 kicks off June 4
The iOS version is apparently rolling out today, with the Android version "coming soon". The company introduced a hidden dark mode for the desktop client in May 2017, around the same time when the service rolled out its cleaner and simpler Material Design-inspired interface. But even with new evidence that the whole app was going dark, it was clear that significant work remained, with some screens stuck in a halfway state: white text, but also a white background. The company did not set a firm date for Android devices to get the new dark theme.
For those who like to watch YouTube in bed at night, this Dark theme will help keep brightness to a minimum, especially if you have a partner who is sensitive to light at night. In a way this is a great option but ...