I myself don't even know what the "KARMA" thing is?!?
Lame, I know!!
Is it like hitting the "LIKE" button on an Instagram picture?
They are "positive" and "negative" points, that can only be given by others, on your profile.
If you give someone good/bad advise or have a good/bad transaction online or in person you can give someone good or bad karma points that are visible under your avi and pic in your posts.
You can also give am explanation for giving +/- karma.
Pretty cool function I think.
Its a feature I personally hope makes its way over to the app one day.
-beerjet-