I'm bumping this old thread to see if anyone has some more recent encounters with purchasing SIM cards upon arrival in Delhi. My family is going to visit various cities across the country and we will all have unlocked phones we just need SIM cards that will work to call back to the US and call each other preferably for cheap and also if possible connect with a BIS or some other data connection.

What should we bring with us when we get to India to make this process easy?

Thanks for your help.