While many Nexus fans laud Google's software navigation button initiative, it's always been a bit irksome that they take up valuable screen real estate at times when they're not really needed. If you're reading a book, watching a movie, or playing a game, the software nav buttons are more a distraction than anything. In fact, until now, only the YouTube app (and perhaps a couple other system apps in certain circumstances) was able to hide those buttons. With Android 4.4, that finally changes.
Full-screen immersive mode is a new feature in KitKat that allows any app to go truly full-screen, hiding both the navigation and status bars. Google also gave the process of getting them back some thought, and has come up with a new gesture for that purpose. In any app in full-screen mode, simply swipe down from the top of the screen or up from the bottom and the status / nav bars will reappear. Tap in the content area (or wait a few seconds), and they'll vanish again.
Considering that wasted screen space has long been a point of software nav button detractors, this comes as welcome news. App developers will have to specifically enable support for the feature, of course, so don't expect the change to happen overnight (e.g., the Kindle app will get it in 2 years).
This is just one of our many KitKat feature spotlight posts today, but if you want a broader overview of the newest version of Google's mobile OS, be sure to check out our Android 4.4 announcement.