No “0” prefix needed to dial to a STD mobile number in india now. All the telecom companies where using the prefix system earlier to make call to STD numbers. For that people need to add “0” or “+91” prefix before the number.
Now the companies are removing this prefix system for STD mobile calls. It will be now easier for Mobile Number Portability (MNP) throughout the country. MNP to and from different circle anywhere in India was introduced in last July, but the prefix system became a barrier for that.
No by removing prefix system customers can port their number from one circle to another. Some of the operators such as MTNL. Vodafone, Airtel already removed prefix system, other operators will make it soon.