Very exciting, though definitely experimental -- while working last week at Mediamatic in Amsterdam, I managed to implement basic spectral matching, which finds the closest spectrum to any new spectral reading you take. Here's a video showing it correctly distinguishing between 2 types of olive oil:
Sadly, the just-released Chrome 20 breaks my code, so it'll be a day or two before I get this running again there. But you can definitely do this with Opera or Opera Mobile for Android.
Update: Chrome 21, just out last week, is much more reliable, and I updated the code so now it works very well! It also has a "waterfall" display which makes measurements much easier.