Cell phones are complex electronic devices, sensitive to heat, cold and excess moisture.
But a cell phone’s sensitivity isn’t limited to extreme weather conditions. Analog cell phones, as opposed to the newer digital phones, can be cloned. This means that someone can tap into your cell phone’s personal identification number and makes calls on the same account. In other words, with a little technical know-how, someone can steal your phone number and charge the calls made to your account. You won’t even know it’s happened, until you get your phone bill.
How does cloning happen if each phone has its own unique identifying features? Whenever you dial a number from your cell phone, the ESN (electronic serial number) and MIN (mobile identification number) of your phone are transmitted to the network, identifying the cell phone dialed from and who to bill. Some people, who work in the way that computer hackers operate, can use a scanner to listen in to this transmission and capture the code. They can then use the information they gather to make calls that are then charged to the account of the phone number they have in effect “broken into.”
For more detail: How are cell phones cloned?