Hey Inkscapers, check this out
http://www.gimpusers.com/news/00462-use-android-tablet-as-graphics-tablet-wi...
A simple use of an android tablet to feed as an extended X input device for drawing in Linux. Needs the X11 driver part to feed the data from the Android device to the X11 system, but from there it should end up working for all apps, including Inkscape.
This is overlapping an area I was working at from the other direction, but should be easy for me to hook up to from Inkscape directly. My talk at LCA 2013 is going to be on that input work (using wiimotes, guitars, gamepads, etc.) and once I get to the point of reading in drawing data (in addition to current use as keys and pressure modifiers) using that should be very simple and avoid the need for any X11 drivers.
Oh, and from what I see of the protocol, it should end up working cross-platform.