Thank you all for the information. For $25 I am going to try it. I've read about how it uses IOS devices with Bluetooth on to report back but have yet to find specifically how close they have to be. @
Tcoat has a great point about the immobilizer and not leaving the keys in it; having a car stolen from a dealership that was later found double parked with the keys in it does not seem as far-fetched to me.