Windows 8.1, the update for Windows 8 with many new features and improvements is scheduled to be released as a preview on June 26during the Build conference. Microsoft has already shared many of the features along with a demo video but, now, the software giant has released a short teaser video for Windows 8.1 Preview launch.
Windows 8.1 Preview on Microsoft Surface

Windows 8.1 is the update for Windows 8 which would be getting new features like customizable Start Screen,deep search integration with Bing, new tiles sizes, more pre-installed apps, Start Button on desktop, usage of desktop wallpaper as Start Screen background and many more.
Windows 8.1 would also be getting finger print login options along with hands-free function mode and revamped Store app to give more exposure.
Microsoft has released a quick 9 second teaser video of Windows 8.1 where you can see the desktop with Start Button and the Start Screen with the same video as desktop. You can also see the different tile sizes and new app tiles as well on Start Screen.
Windows 8.1 update would be available for free from Windows Store and when the update is released as a preview on June 26, you would get a notification that the update is available.