sorry for my noob question, but can you clarify what you do mean with CPA and Affiliate Marketing? What's the difference?
Up to my knowledge:
CPA = cost per acquisition i.e. you get paid for some action performed by your visitor (app install, mail submit, etc..)
Affiliate marketing: broader. You get a commission on anything (example for a sale, like revenue share).
Maybe in this context these words have a different meaning?