there is a new app called "SnoopSnitch" (https://opensource.srlabs.de/projects/snoopsnitch)
that visualizes network anomolies imposed by rogue mobile phone base stations, or by people
subscribed to services designed to snoop on your phone through SS7 trickery.
Sadly, your ROM does not support /dev/diag for Qualcomm, while in theory, given HD2 uses
this chipset, it should work. I dug around and what is probably missing are these settings:
I am using NexusHD2 2.7 and would be delighted to hear some feedback if enabling them is
possible on the older version or the latest.