which is the best affiliate program?

Alex, this is such a broad question, it would be impossible for anyone to answer unless knowing more about your site, your traffic sources, and the quality of your traffic.

What I can tell you though, if you're looking for top performing CPA networks with high converting offers and custom ad tools - our program at CrakRevenue is a popular choice for many.
Moneysmart Network gives a capable Cost for each business Network which helps you pick up additional wage by reducing your upkeep of ads. Our dumbfounding customer assistance and business examination sets our customers above their adversaries. Moneysmart Network is a proficient methodology to adjust your site with our super snappy CPA Network.