I purchased the Ubuntu Phone (bq Aqaris E4.5) and if you download a terminal app for the ubuntu Phone and type in
service --list-all a service named
x11-common is listed as well.
But typing in
Xorg just returns that the command was not found.
If you search for "ubuntu touch x11-common" you'll find this:
X Window System (X.Org) infrastructure
x11-common contains the filesystem infrastructure required for further installation of the X Window System in any configuration; it does not provide a full installation of clients, servers, libraries, and utilities required to run the X Window System.
A number of terms are used to refer to the X Window System, including "X", "X Version 11", "X11", "X11R6", and "X11R7". The version of X used in Debian is derived from the version released by the X.Org Foundation, and is thus often also referred to as "X.Org". All of the preceding quoted terms are functionally interchangeable in an Debian system.
This means that you will NOT be able to run windows from your 'normal' OS.
"The phone becomes a full PC and thin client when docked."
This is only true for the Ubuntu Edge, which did not succeed to be funded. It might be realised in the future though. At the current state (early 2015), the bq Aqaris E4.5 does not even support OTG HDMI, while basic OTG USB Keyboard and Mouse support already works.