Tata docomo is very weak service provider .many time its network has lost and its calling facility is so weak too much low bandwith network.it has slow network speed. when I surfing with internet network always very slow even my network is 3G. when somebody calling me it say the number you have dialed it switch of or out of service.please do not buy any service by tata docomo. because it has less and no better service in its network service.