Many Indian mobile users have all operators3two to three mobile numbers, reasons may be many but one could be low call rates or free calls on On-net numbers. Indian users use their mobile number very intelligently, If one user has one SIM of Reliance and other SIM from Vodafone then to make a outgoing call to a person having Reliance number, user originates call from his Reliance number. I hope you got my point.
But keeping so many SIMs of different mobile operators, you need to know their different USSD codes for checking your desired information. You always try to ask the representative of that particular mobile operator but even then you may not get right codes.
