Companies aren't just tracking you online; they track your movements in stores, airports and other locations. This is done using the unique Wi-Fi or Bluetooth MAC address from your mobile gadgets. Click here to learn more about how retailers use MAC addresses to track your movements.
Why? They want you to buy things. They want to know how you shop, what you shop for, and they use that information to serve you targeted ads.
It's a little intrusive to say the least. What's even more alarming is that most people aren't even aware that this is going on.
However, when Apple users update to iOS 8 when it's released in August or September, they won't need to opt out of this kind of tracking.