I have been trying both of these apps for ceiling my mobile. Result was in favour with OLX. Even though OLX pets fewer features than Quikr OLX came out to be best.
I posted the same ad of mobile on both the websites and there was no response from Quikr not a single person viewed my ad but on the other hand there were more than 25 peoples who wanted to buy my phone.
I like the chat feature of OLX its turned out to be better than Quickr and I was able to bargain better on OLX.