3g and 4G do not differ much. $g is only an advancement over 3G. Reliance is said to be working towards 4G. I have Tikona net connection that claims to be using 4G technologies. $g will enable using internet in cars, trains etc. in better way.
http://en.wikipedia.org/wiki/4G
G. K. Ajmani Tax consultant http://gkajmani-mystraythoughts.blogspot.com/
3G is working in allover network but 4G is coming but not available now.Than 2G now 3G is better with some extra facilities and 4G will be more better.
