"3G services in India have surpassed the world average in terms of growth. However, there are still gaps in 3G coverage even in the top 50 towns. Filling of those network coverage gaps can take up 3G penetration dramatically," NSN's vice-president and head of India Region Sandeep Girotra said in Delhi.
According to NSN, 3G data usage in India rose to 21 petabytes at the end of December from 8 petabytes at the end of December 2012. One petabyte is equal to 1,024 terabytes. The world average is roughly doubling every year, it said.     

Data traffic generated by 2G and 3G services combined grew 87 percent in the country in 2013, driven largely by strong growth in the faster 3G data, the study said. NSN's Mobile Broadband India Traffic study showed that customers in India consumed an average of 532 megabytes of 3G data every month, up 23 percent from 434 MB in 2012.
The average consumption by 3G users was more than three times that of 2G consumers, which stood at 146 MB per month. Last year, 3G continued to be the main contributor to data growth and increased its share to 43 per cent of total mobile data from 33 percent in 2012.
The active 3G customer base grew by 50 percent. The study estimates the number of 3G customers in the country at about 30 million at the end of December 2013 compared with 20 million at the end of 2012.
Girotra said there are about 80,000 mobile towers that transmit 3G signals, accounting for 30-40 percent of coverage in the country and there can be a dramatic increase if coverage goes up to 70-80 per cent. India has about 4,50,000 mobile towers providing 2G services, Girotra said.
"Even in the top 50 cities by mobile traffic, many cities are not fully covered by 3G and require an additional 20-25 per cent of existing sites for coverage," Girotra said. With 4G technology maturing, telecom operators are now looking to deploy 3G equipment that can be upgraded.
"I expect 3G to be mainstream mobile Internet service for at least 2-3 years, after which we will see a mix of 4G and 3G. 2G, too, will continue in the country," Girotra said.
NSN at present manages about 1,60,000 mobile towers in the country. The network managed by the company handles traffic of about 280 million active customers.