Not possible in Construct2 so far if ever.
Augmented realities is something i had a play around with in AS3(programming language) there really hard to work with, Let alone making a game out of it.
there was only 1 game i ever heard about on the IOS market that used this(Before i saw this one) And it was only compatible with the IPad2, It takes allot of performance.
I guess if you was a scripting genius you could somehow make this with server side scripting. then use ajax to request it in C2.
Good luck! <img src="smileys/smiley1.gif" border="0" align="middle" />