Well I got my antenna in the mail today and did a quick test in the drive way.
I'm using MotionX GPS available from the iTunes App store for a small fee, there is also a free version that has all the features of the paid version but it only lets you have one saved track. The App doesn't have a display screen that would give me a good detailed look at the satellite information. All it does is tell me that I either have a weak signal, a low signal, or a good signal.
What I did first was put the iPhone in it's holder located in the cup holder of my center console. I then started up the GPS program and let it go through it's cycle of looking for satellites. Like usual the signal was weak and only the cell tower triangulation was able to provide a general fix on my location. After a few minutes of not finding a signal the program asks if I want to keep searching for satellites and I clicked the button to keep searching.
Then I pulled the active antenna out of the package and placed it on the roof (for some reason magnets don't stick to aluminum rover roofs) and immediately noticed that the signal improved going from Weak signal to Low Signal. Not really sure why this had this effect but apparently just having an antenna in the vicinity helps a little bit.
Then after plugging the unit into the cigarette lighter and clipping the passive antenna on to my visor the signal went from Low to Good Signal.
I repeated this a few different times to make sure that it wasn't just a freak accident that I managed to get a signal in my vehicle. One thing I observed was that just having the antenna in the vehicle is enough to get a Low signal on the unit after it has already acquired satellites and received a good signal. I would notice this after confirming that I had a good signal with the unit plugged in and then un-plugging it to put it away. After it was un-plugged I would pull the antenna in off the roof and start packing it up. The whole time the signal was low. It wasn't until I removed it from the vehicle did the phone lose it's signal.
So I guess I can say for certain that this thing really works and that the snake oil rumor is false. It was mentioned that it is illegal though. I suppose that is sort of a down fall.
I plan on testing it again with a stand alone gps unit that displays graphic satellite information so I can get a better idea of how well it works.
