Slowdown failed to hit rising mobile usage as Indian GSM operators added a record 9.1 milliom subscribers in February, taking total users to 277.1 million, thus, maintaining rapid expansion in the world's fastest-growing wireless market.

Bharti Airtel Ltd [Get Quote] led the signings, adding 2.73 million subscribers in February to take its mobile customer base to 91 million. Vodafone Essar Ltd, controlled by Britain's Vodafone, added 2.5 million users in the month, to take its subscriber base to 65 million, data from the Cellular Operators Association of India showed.

Bharat Sanchar Nigam Ltd added 1.5 million users in February taking its total to 44 million. Idea Cellular [Get Quote] gained 1.5 subscribers as well, and now has 41 million users.

There are five other companies that offer GSM services, including Reliance Communications Ltd [Get Quote], which has majority of its subscribers on the rival CDMA network, and announces its subscriber additions separately.

India's mobile market is booming, thanks to call rates as low as one US cent a minute, the availability of cheap handsets and expansion of networks to smaller towns and rural areas.