Vodafone idea (Vi) giving 1 GB 4G data to every VI users by dialing a number only . You can activate 1 GB data offer two times in a month which gives you 2 gb data each month for free.
How To claim 1 GB Free 4G Data in Vi:
- First dial a number 121249 from your Vi SIM.
2- Now you will hear 1 GB offer detail .
3- Now press 1 to activate it.
4- Bingo ! Free 1 Gb vi data will credited instantly .
Important Points 
This data comes from 1 day availability
You can activate it two times in a month on single number.
If you did not hear offer detail on call then you are not eligible for free data.