Source: http://gizmodo.com/5574423/16gb-iphone-4-parts-cost-18751
The components that make up the 16GB iPhone 4 cost just under $188, according to iSuppli. For some perspective: that's more than Droid or the 3GS. Most of that added price seems to be built into that fancy retina display.
That screen—likely produced by LG—cost a disproportionate $28.50 per unit, according to iSuppli. The A4 processor—from Samsung, and the same as in the iPad—cost $10.75, and the new gyroscope chip came in at an estimated cost of $2.60.
It's not clear how much profit Apple's clearing with each unit—iSuppli doesn't take into account the marketing, design, manufacturing, etc. costs, or how much AT&T contributes—but it's safe to say it's at least in line with previous models. [Businessweek]