Apple gained share and posted the third-highest growth rate of any top five mobile phone vendor but dropped to the number five position globally, according to a new IDC report (http://www.idc.com).

Global iPhone shipments declined sequentially during the same quarter that company founder Steve Jobs handed the CEO reins to Tim Cook, according to the research group. The decline, not coincidentally, happened as Apple readied itself for the 4S launch, which many waited for. Apple’s ability to upgrade 3GS users to the 4S, for example, and make continued inroads into developing economies, where it has been less successful, will help dictate the company’s smartphone fortunes in the future, according to IDC.

The research group says Apple has 4.3% market share globally; that’s up 21.3% year-over-year. Ahead of it are Nokia (27.1%), Samsung (22.3%), LG Electronics (5.4%) and ZTE (5.4%).

The worldwide mobile phone market grew 12.8% year over year in the third quarter of 2011 (3Q11), as smartphone growth declined in key mature markets. According to the (IDC) Worldwide Mobile Phone Tracker, vendors shipped 393.7 million units in 3Q11 compared to 348.9 million units in the third quarter of 2010. However, the 12.8% growth was higher than IDC’s forecast of 9.3% for the quarter and stronger than the 9.8% growth in 2Q11.

— Dennis Sellers