Hi,
have you seen the new Logitech Arx Control solution?
It's basically a way to use iOS and Android phones and tablets to display and control various stuff of your gaming PC.
The only requirement - besides the phone or tablet - is to have Logitechs Gaming Software installed. It works with all Logitech keyboards and mice that are supported by the Gaming Software.
And, as far as I understand, there's a documented API which allows you to display custom stuff in the app. I haven't looked at it, but I guess it's not too different from the API that they used for their LCD