Do you have a smartphone and you are using the old Airtel SIM? You can upgrade your Airtel 3G SIM to 4G and get free data up to 10 GB. You can complete this process both online and offline. So let's know about ways to convert Airtel 3G SIM into 4G. Instantly Upgrade Airtel 3G SIM to 4G Before you upgrade your Airtel SIM, I will tell you that your Android phone should also … [Read more...]