iFixit has a run down of all iPhone components here which includes some datasheets.
Following is a tear down graphic by Semiconductor Insights reported about here.
Top side
Bottom side
Testpoints Exposed
Important differences from the internals of original iPhone
- Battery is no longer soldered.
- CSR Bluetooth chip updated to BlueCore6-ROM [Archived 2011-05-25 at the Wayback Machine]. See Datasheet [Archived 2014-07-03 at the Wayback Machine] If you know what BT profiles this chip supports, please add.
- (Anyone have more? please add)