Aircel which was predominantly present in TamilNadu is now available all over the country. They have Dhoni as brand ambassador. Launched 3G services recently.
To activate Aircel 3G:
1) SMS “START 3G” to 121 from your Aircel Mobile
or
2) Submit the form at their official site
To deactivate or stop 3G in Airel:
Just SMS “STOP 3G” to 121