The world has gone global that most things are possible through technology. Smartphone produced have its simcards, phone numbers that are registered with some specific network like Mtn, Glo, Airtel, 9mobile, and starcom in Nigeria.
All this network has a similar procedure of registering the phone number before it could be use for on-line real-time work.
This registration includes picture capturing, address, state, occupation, sex, next of kin, means of identification like voter's card to be certified that you gave a proper information about yourself.
Tracking of the exact location of a caller is very easy if you meet the network provider of the caller and it's also easier if the GPS in the callers phone is on during the call.