[AC Question]

the Android OS, obviously, drives the Screen on(within) the Phone/Tablet..

can it drive a second/auxillary Screen? preferably, via Wireless I/O..

also, if that can be the case, is it possible to put the 'Main' Screen in "Sleep"-mode (while driving the aux. Screen)..?

[B. Diddy]

Welcome to Android Central! I don't think so. There are a number of apps that allow your phone or tablet to be an extension of a computer display, but not the other way around.

[Rukbat]

Chromecast will cast the screen to any monitor/TV with an HDMI input. Only the complete screen and any and all apps for certain phones/tabs - Chromecast mirroring - but there are a a number of apps that support mirroring the app (so it only mirrors to the other screen when that app is running) - Chromecast supported apps.

If your device is on (or close to) one of the phones in the list (they keep adding devices), or if the only apps you want to mirror are on the supported apps list, buy a Chromecast. (The app to mirror the device is at Chromecast - I don't think there's a link to it at the first link I posted.) The screen on the device can go black and the Chromecast screen will still show.