Congratulations to you for your article anyway, it's an opportunity for people to know sites they weren't aware before.
There are some interesting concepts there too such as FOAP.
Getting a cash back is not a big deal but there is nothing like a application that gives you free money, any application you install and gives you cash back or anything free, they are not doing that just for their promotion alone they will be selling you information to companies that wanted them and these companies will give you shit crap for providing your sensitive information.