You can (I have it installed on my LG G Pad), but I doubt PS Touch will support a pressure sensitive pen, the focus is on pressure sensitive screens rather I guess. Regardless I'd also be interested in such a stylus if they where not to pricy.I was just looking in to this today. I would like to know also. PS, can you use Photoshop Touch on G Pad?
Im actually using a crappy stylus that has some kind of dry rubber thing at the tip and it works great. I use adobe acrobat reader to highlight stuff