You're app and device look pretty cool.

One thing struck me as odd in reading your home page. It looks like you're marketing to the paranoid people.
(As opposed to making it sound like something people can't live without. Like "So, you just ordered flowers for mum and you want to know when they will arrive? Well, as a florist, you can now track the location of your delivery person!" Improve customer service! Happier Customers! The GPS Tracker is an affordable system for you!")

Okay, so I'm not a salesman either. But it's my 2 cents about what jumped out at me when I first loaded your page.

(I'm curious how you built the GPS, which is why I looked in the first place.)