Also known as the scamworld, The Verge wrote a great article about this four years ago:

http://www.theverge.com/2012/5/10/2984893/scamworld-get-rich...

Sadly,the writer of that article has since left tech journalism and Salty Droid, one of their main sources for the article and a blogger who writes to expose the scam that that industry is, is now considered to be "an extremist" for his work by The Verge.