What kind of WiFi Antenna is that Iphone uses?
I don't think this actually is just an antenna, looks more like a composite device made of multiple things.

Anyway,

As explained in my last answer, antennas in phones are the results of long optimization, simulation, optimization, new constraints, … cycles. You won't see a "pure-bred" PIFA, dipole, … in the wild; these antennas are typically a mix of a lot of things, due to the trade-offs they make.