Originally Posted by glennQNYC
What makes me skeptical that the snap-in adaptor makes an iPhone utilize the external antenna is I have never heard of ANY device (car or home) having this functionality. Since we know it there isn't a hard-wired connection to the antenna, the only plausible explanation would be a cellular repeater.... And that wouldn't require you to snap the phone into anything. I chalk it up to marketing BS. I think the marketing dept is recycling bullet points from the days when Motorola Flip Phones had an antenna connector on the back and docks did that kind of thing.
Well there is this
And there is actual testing (done by me)
and if you search hard enough, someone once posted the actual BMW design of it and how it worked.