They have got some patent on this. it was published on Mashable as well as TechCruch.
*www.google.co.in/url?sa=t&rct=j&q=...qyKbzU96LpvMQ6WMA&sig2=7vDv7cRlvzFWoazjBWdQcg
*www.google.co.in/url?sa=t&rct=j&q=...W6_buZe54937nOoug&sig2=01sNG78y5sZgyB_6xlzz2g