Don't know if any one has seen this already or not, but I just happened across it..
It's a fairly new $3 app currently only available for Ipads or Iphones, but coming to Android in January. It's called "Architecture of Radio", and what you do is point your tablet in whatever direction and you can visualize the radio waves being emmitted in that area.. 
Apparently, based on a few comments from people who have actually used the app, it's really attractive and cool, but not all it's cracked up to be. It doesn't present in real time, and if I interpret correctly; it shows nothing more than just a pretty picture.. I don't know, I don't have an ipad. Nevertheless, it's a super neat idea. I'm suspect many of us at one time or another have fantasized about having a way to actually see our transmission signals!
Someday..
But, I would suppose it's only a graphical representation of known radio sources such as licensed services. After all, do IPADS or IPODS have AM/FM/SW receivers in them? The app probably just plots the "RF" images based on distance from the known sources using your GPS location and FCC database info as a reference.
Your guess is not far off.. However, upon further reading I notice it doesn't even use databases of radio stations (oddly enough) It's focus is on cell towers, wi-fi routers and satiellites.. They really should have incorperated radio stations as well - seems silly not have done so!
The video of it iin use was cool though.
".. Based on your GPS location the app shows a 360 degree visualization of signals around you. The dataset includes almost 7 million cell towers, 19 million Wi-Fi routers and hundreds of satellites.. ..We can’t see radio with our eyes. The waves that we use for our cell phones and Wi-Fi are way outside the spectrum of visible light. In order to “see” radio.. ..but it will always be an interpretation..."