In a blog post, Google said:

“Dark theme will intelligently adjust the product interface and user-generated content in ways that can make it more usable in low-light environments and save battery life.”

Put more elegantly than we ever could.

It means that the apps should intelligently adjust depending on your phone’s dark mode settings, but you’ll be able to toggle it on an off for each app. We’re still not sure if we’re ready to see a spreadsheet in black.

The slowness in rolling out dark mode goes to show that it’s not as easy as just reversing all the colours – far from it. Developers are clearly taking their time in honing dark modes for apps, particularly as apps as popular as Facebook still don’t have the feature globally.

But now you can fiddle those spreadsheet numbers into the wee hours when you should be sleeping without a blinding white screen lighting up the room. Google says the change will take about two weeks to completely roll out globally.