Apple Inc saw its revenue from greater China - which includes the Chinese mainland, Hong Kong and Taiwan - plummet 43 percent in the fiscal third quarter ended June 29 from the previous quarter and 14 percent from the same period last year, according to the company's quarterly report published on its website Wednesday.

"The main cause of the decline in revenue is the company's lack of innovation in its products," Shen Zheyi, a research director at research firm Gartner, told the Global Times Wednesday.

In both appearance and function, Shen said Apple "has made almost no breakthroughs" for its products such as the iPhone since 2007.

Although Apple CEO Tim Cook said in the press release that "we are really looking forward to the amazing new products we've got in the pipeline," some Chinese users who were once fans of Apple cannot wait any longer.

"There are more choices of various types of smartphones and tablets than before, and Apple is not irreplaceable and unique anymore," Zhang Yang, a 32-year-old engineer in Beijing who has bought two ­iPads and three generations of iPhone, told the Global Times Wednesday.

Zhang compared the iPhone 4 with the iPhone 5, saying that "there is almost nothing different between the two devices for [Chinese] users."

As well as a lack of innovation in its technologies and functions, "serious competition from competitors such as Samsung and HTC is also a cause of Apple's poor sales performance in the third quarter," Cao Yujie, director of consultants for IT market research agency CCW Research, told the Global Times Wednesday.

"Apple's brand popularity with consumers is not as high as before," Cao noted.

Apple's revenue not only declined in China in the third quarter, but also dropped by 19 percent across the world, the company's report said.

Although worldwide sales of Apple's most popular device, the iPhone, rose by 20 percent in the third quarter compared with the previous quarter to reach 31.24 million units, its iPad saw a 14 percent decline while the iPod fell 32 percent.

"Apple has come up against a global challenge indeed," Cao noted.

Tim Cook was quoted by Reuters as saying Wednesday that the shortfall was partly due to the economy and said he remained bullish on China.

Apple China could not be reached by press time Wednesday.

China has become one of the most important markets for Apple.

Greater China accounts for around 13.1 percent of the Silicon Valley giant's third-quarter revenue, according to the company's report.

China has exceeded the US to become the world's largest market for smartphones and tablets, data research agency Flurry said in a report this February.