There was a time when I had traffic that did not convert at all in the marketplace, let's say, quite a lot of mobile traffic almost for free. I tried a lot of marketplaces and WAPs, then I switched to Kingfin. I used Kingfin and converted! Of course, it is not super, but considering almost free traffic, I earned $3k for a couple of months and then a bit more every month! I was only pouring traffic for 1 month. They paid out everything and still paying, it's been almost a year.