The line separating the mobile and desktop computing worlds has become increasingly blurred in recent months, and HP on Monday unveiled a brand-new all-in-one PC that continues that trend. Announced during its HP World Tour event in Beijing, the HP Slate 21 tablet is powered not by Windows but by Google’s Android. It’s also designed for use on the desktop, with a kickstand in back to prop it up. The HP Slate 21 is due to begin shipping in September; pricing will be $399. 
