There are already quite a few “solutions“ that do this. They are all rather poor. As was stated in the article, Android is designed around a touch interface which doesn't easily translate to keyboard and mouse input
Posted Feb 22, 2012 16:00 UTC (Wed) by Cato (subscriber, #7643)
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Combining a physical keyboard and monitor (but no mouse) with a tablet is feasible (Bluetooth or USB work, even on an iPad, via the Camera Kit) and in fact quite a few iPad users do this, mostly when they want to actually write something significant.
I'm looking at this for someone who is finding even a locked down PC too complex (multiple tabs and windows create great confusion), and needs more of a kiosk/tablet type experience.
For a smartphone, Ubuntu for Android may make sense, but for tablets you might as well use the native tablet apps on the tablet screen, and just add a keyboard as needed.