A woman looks at the Apple iPhone 7 at a shop in Seoul on October 21, 2016. Jung Yeon-Je | AFP | Getty Images

The shine may be coming off Apple's business in China, but that's not its only market in the Asia Pacific region. The Cupertino, California-based technology giant sent a shudder through global markets after CEO Tim Cook's letter to investors released on Wednesday showed the company lowered guidance for this year's first-quarter on China's slowing economy and weaker iPhone and other device sales there. Greater China was Apple's third-largest market in terms of revenue in the fourth quarter of 2018 — after the Americas and Europe — at $11.4 billion, according to company figures. The figure for Japan ($5.161 billion) and elsewhere in the Asia Pacific region ($3.429 billion), meanwhile, came to $8.59 billion. The company did not provide a breakdown for other countries. Outside of China, Apple has done well in mature and wealthy economies such as Japan, South Korea and Singapore, where its pricey phones can be more readily afforded. But in the rest of Southeast Asia and India, where overall economies are growing but per capita incomes remain relatively low, the going has been tougher.

Japan and South Korea

Japan and South Korea are wealthy economies and also two of the most mature smartphone and mobile device markets in the world. Apple has made strong inroads in both, leading market share in the former and coming in second in the latter. In South Korea, Apple's road to success has been more challenging, given the dominance of local manufacturers Samsung, the world's top smartphone seller, and LG Electronics.

Still, figures from web analytics company StatCounter show that Apple consistently ranked No. 2 in the South Korean market last year behind Samsung and ahead of LG. But Japan and South Korea are two of the world's fastest aging societies, so it remains a question mark how much they can contribute to the company's success in coming decades.

Southeast Asia

Southeast Asia, with a population of more than 600 million, is potentially a huge market for Apple. The company had top market share of 39 percent in city-state Singapore as of the end of the third quarter last year, according to research firm IDC. But in bigger economies such as Indonesia, Thailand and Vietnam, it lags behind rivals. In Indonesia, where Apple has about 1 percent of the market, and most other countries in the region, its phones are simply too expensive for most consumers. "That's the biggest factor," said Kiranjeet Kaur, research manager for IDC in Singapore. That leaves most buyers with little alternative but to go for cheaper South Korean and Chinese models, she said.

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