Airtel is the number one mobile network provider in west Bengal. I am using this sim since I phone have.
I live in kolkata and I can use 2G 3G and also 4G network.
network services is really good its always high in kolkata and it also good rural area and its surprising me that I get network on metro rail. The net serfing is really fast and net pack is also affordable to all. They give nice offer by messaging and calling. Its really good service operator. you can use it.