Windows Phone and Windows 10 Mobile users can change the entire look of the OS to a "dark theme" in its settings. Now a new report claims that the dark theme option is finally coming to Windows 10 on the PC side as part of the big Anniversary Update later this summer.
At Build last week, Gabe Aul hinted that a dark theme will also arrive with this update and after asking around, I was able to confirm that the internal builds Microsoft employees are using have a 'dark theme' toggle in the Settings menu. When you enable the theme, it turns everything not colored by your personalization color to the darker setting and is system-wide.
While some Windows 10 apps have the option to turn on a dark theme, this rumored update will allow the entire OS to have that option as well. It's likely that it will be available in an upcoming Insider preview build before it is launched with the Anniversary Update.