tracker

Another name for your smartphone since it is actually a tracking device that happens to make calls, take pictures, play music, and buy things, among other uses. 

Thanks to the explosion of GPS technology and smartphone apps, our devices also take note of what we buy, where and when we buy it, how much money we have in the bank, whom we text and email, and so much more. Cellular systems constantly check and record the location of all phones in their networks, so if someone knows exactly where you are, they probably know what you are doing.