As mobile phones reach more of India's gigantic population, one of the challenges facing both users and service providers is the country's linguistic diversity.

The number of mobile users in India has grown explosively to more than 900 million today from about 4 million in 2001, according to the Telecom Regulatory Authority of India. Most of the handsets available in the market feature qwerty keypads that are easy to use for the country's urban, English-speaking population. But these keypads could be tricky for many others in rural areas who speak only regional languages.

While many rural Indians who don't have fixed-line phones at home use their cellphones for voice calls, lack of support for local languages on mobile phones often prevents them from using text messages, address books, Internet browsers and other mobile applications that require them to type letters as well as numbers.

India has 22 major languages, with nine different scripts. Each script is represented by scores of characters. Typing each character on a basic mobile phone involves multiple tappings on the keypad, which can be cumbersome.

Analysts say some of the latest models of smartphones to be launched