At the time of the iPhone launch in 2007, Apple's profit margins were at 15.4 percent, while Foxconn's was at 2.7. In the most recent quarter, Apple reported 30.8 percent margins -- double what it was 4 years ago -- with Foxconn at a mere 1.5 percent.
Foxconn has continued to grow with the tremendously successful launches of new iPhones and the iPad. The company has sacrificed margin growth so it can get volume and scale, something very important to Apple which puts extraordinary pressure on its suppliers for low prices.
While Foxconn's margins are extremely small in comparison to Apple, they do exceed those of a number of categories, including grocery stores and the global shipping industry.