London (CNN Business) 1. Apple earnings: Has Apple (AAPL) moved beyond its China problems?

That's the big question from investors as the company prepares to report earnings after US markets close on Tuesday.

Apple warned investors in January that iPhone sales had been hurt by the slowdown in China's economy and an ongoing trade war. But CEO Tim Cook noted signs of improvement last quarter, highlighting the positive response to lower prices in Asia. Shares are up 10% in the past year.

Wall Street analysts are divided about whether Apple can turn its iPhone fortunes around. Jun Zhang, China analyst at Rosenblatt Securities, has predicted that the iPhone XS will wind up being "one of the worst selling iPhone models in the history of Apple."

The specter of fresh tariffs also looms. US President Donald Trump has said that if his administration goes forward with another round of duties on Chinese exports, he will refuse to exempt Apple from levies on parts for the new Mac Pro, which Apple reportedly plans to make in China.