Remote Packet Capture on iPhone

Step 1: Plug your iOS device into the USB port of your Mac
Step 2: Use the Xcode organizer to obtain the UDID of the device

# Mount virtuel network interface:
$ rvictl -s <UDID>

# List active devices:
$ rvictl -l

# Use wireshark or tcpdump:
$ tcpdump -n -i rvi0

# Unmount virtuel network interface:
$ rvictl -x <UDID>

Every IP packet sent/received by iPhone is mirrored on this virtual interface.