FRAMINGHAM, MA – Second-quarter sales of cellphones grew 65.4% worldwide year-over-year to 106.5 million units.

It was the third straight quarter total shipments exceeded 100 million units, International Data Corp. said.

Among smartphone vendors, Apple took over the top spot in sales, beating out Nokia. It was the first time Nokia was not the quarterly leader.

"Ever since the first iPhone launched in 2007, Apple has made market-setting strides in hardware, software, and channel development to grab mindshare and market share," IDC said. "Demand has been so strong that even models that have been out for one or two years are still being sought out. With an expected refresh later this year, volumes are set to reach higher levels."

The research firm maintained its growth forecast of 55% in 2011. "The first half of the year has demonstrated strong growth for the smartphone market," added Llamas. "The second half of the year will bring new flagship models and refreshed user experiences to market."

IDC said Apple's distribution, increased manufacturing capacity and broad-based demand contributed to its performance. No. 2 Samsung showed the largest year-over-year growth. Meanwhile, No. 3 Nokia has been slow to get its Windows-based phone to market. No. 4 RIM has been slowed by a lack of new models and stronger competition for its traditional business customers. HTC launched and announced several new models during the quarter, and is "well poised" to reach its goal of shipping 50 million units for the year.

Table 1. Top 5 Worldwide Smartphone Vendors, Q2 (shipments in millions)

Source: IDC Worldwide Mobile Phone Tracker, August 4, 2011. Vendor shipments are branded shipments and exclude OEM sales for all vendors