The mobile handset market is very volatile and this gets proved by the fact that ZTE de-throned Apple to become the 4th largest handset manufacturer in 2010. As a result Apple has gone down to become the 5th largest Handset manufacturer and RIM does not even feature amongst the Top 5.
Nokia leads the pack with 453M handsets shipped in the year 2010. ZTE shipped 51.8 Million units and Apple shipped 47.5 units (handsets) during 2010. Here are a few figures that give you a detailed idea of the units shipped and the market share of the top 5 handset manufacturers.