
Android 4.2

Android 4.2 aims to take the speed and simplicity of Jelly Bean to a new level.
List of New Features
Gesture typing

This version of Android received a new keyboard, in features very similar to Swype.
Miracast Support

The ability to stream wireless HDMI to transfer video from the device (it doesn’t matter if you watch a video on YouTube, TV or video from the device itself) to a high-definition TV.
Support for multiple user profiles

Now the tablet or phone will be able to store several user accounts and their personal settings in themselves and quickly switch between them. Moreover, even the progress in the games for each user will be saved. For this, the multitasking function is used.
Spherical panoramas

Photo Sphere allows you to create spherical panoramas from photos. Which can then be immediately downloaded, for example, on Google Maps.
Active notifications

A single space for all received notifications + the ability to perform actions directly from this notification panel.
Daydream

Display background applications while the device is in standby mode or in the dock. For example, photo albums, news from subscriptions, and more.
Live it now
The ability to automatically provide the necessary information. For example, you are standing on the railway platform, and the smartphone itself tells you which trains will be here soon. Or shows photos of popular places nearby. In general, here's a video for you.
Full list on the official announcement page