A few questions about iPhone 4

Hello,

I have a few questions regarding the parts inside the iPhone 4 CDMA. 1st, what do the two "grounding clips" at the top of the device near the camera (gold in color) ground specifically? I didn't think DC needed to be grounded to anything but the battery. Second, there are two connections that are not used by default, towards the bottom, round connector, similar to the connector on the speaker assembly. What are they used for? If there are specific names for either of these things, let me know, I don't like to butcher names.

Thanks for helping me in my curiosity!