As part of Android O Developer Preview 3 from June, the Google Camera app was updated with a handful of new features. That version is now finally rolling out to all through the Play Store for current Pixel, Nexus, and Android One devices.
Previously, switching between camera and video functionality required a swipe on the viewfinder with an indicator just above the capture button noting the current mode. Version 4.4 simplifies the process by adding a button besides the shutter to switch between modes. Users are still able to swipe, but this new interface is much more explicit.
The next addition in version 4.4 is a very useful tap to zoom gesture. Double tapping on the viewfinder — in either camera or video mode — will zoom in 50%. Repeating the gesture, regardless of the zoom level, will automatically zoom out.
This, of course, is much more convenient than having to pinch in/out and a quicker way to bring up the zoom bar.
Lastly, this update slightly tweaks the button used to switch between the rear and front-facing camera. Version 4.4 is now rolling out via the Play Store to supported Pixel, Nexus, and Android One devices.
More Info: 9to5google.com