Several mobile operating systems support some kind of notification indicator for applications on the home screen. iOS has had notification badges for years now, and one of Windows Phone's most recognizable features are live tiles. Starting with today's O Developer Preview, Android will now officially support notification badges on home screen icons.

This lines up with a previous rumor that Android O would have iOS-style notification badges. Of course, several OEM skins and replacement launchers have implemented their own notification badges over the years, but now it is supported directly in the OS. Visiting the info panel of any application from the settings reveals a new 'Show badge' toggle, as seen below:

Applications have to opt-in to use this feature, and as such, no third-party or system apps have been updated to support it yet. Hopefully we'll start to see apps use this soon, so we can get a better idea of how it works.