Apple sells 48 million iPhones worldwide in Q4

Apple Inc painted a rosy picture for its new iPhones on Tuesday, but a sequential slowdown of overall sales in China cast doubt on the strength of its business in the world’s most important market for smartphones.

Apple’s quarterly sales in Greater China nearly doubled from a year ago to $12.52 billion, accounting for nearly a fourth of its total revenue. But that was lower than the previous quarter, when Apple notched $13.2 billion in revenue there.

The sequential decline is important as many analysts believe China is poised to replace the United States as Apple’s biggest market. Here’s a look...