Apple Inc's share of the Chinese tablet computer market may drop by the end of this year due to the rapid growth of the overall market and the launch of devices by rivals such as HTC and Motorola, a Beijing-based research firm said Wednesday.

Apple's iPad is forecast to take about 70 percent share, a drop from 74.3 percent in the second quarter of this year and 80 percent last year, said Sun Peilin, an analyst at Analysys International.

"The whole market will (also) grow bigger and more diversified in the next several months," Sun said during a phone interview yesterday.

In the second quarter, iPad's market share fell below 75 percent for the first time to 74.3 percent. Chinese vendor EBen ranked second with a 4.8 percent share followed by Samsung's 4.5 percent, according to Analysys. The iPad 2 accounted for 71.7 percent of all iPads sold in China in the second quarter.

HTC, Dell and Samsung have launched tablets with a 7-inch screen on the Chinese mainland. Apple's tablets have 10-inch screens.