Sprint, which is offering the iPhone for the first time, has said that record demand for the new iPhone 4S gave the carrier its best ever sales day for a device family across web, retail and telesales channels.

Fared Adib, product chief at Sprint, said that demand for the iPhone 4S, which is the first iPhone available through Sprint, went beyond the company's expectations.

Speaking about sales on Friday, Adib said that it was “the best ever day of sales in retail, web and telesales for a device family in Sprint’s history.”

However, he attributed high demand to the company’s attractive pricing plan, which promises unlimited internet data for new customers.

Sprint is the newest US carrier to offer the iPhone. AT&T has been offering the iPhone since the first model was launched in 2007.

Verizon Wireless, a joint venture of Verizon Communications and Vodafone Group, started offering the popular smartphone from earlier this year, starting with iPhone 4.

Shares in Sprint gained 0.7 per cent at $2.81 in the after hours trading.