Airtel has recently been giving free Mb to surf the internet1. *141*13*200#
then wait for a reply saying Congratulation dear airtel user you have been giving 200mb for 14days
Insert the sim on your pc and start browsing or you can as well use your phone
CHECK BALANCE WITH *141*712*0#
if you are lucky your sim will get 200mb +100mb + 50mb = 350MB
If you have a fairly lucky sim you will get 300mb - 100mb
if you dont have a lucky sim you will get 50mb downward.