London (CNN Business) 1. iPhone trouble: Apple said Tuesday that its revenue for the first three months of 2019 declined 5% to $58 billion. The big problem? Smartphone sales for the period fell 17%.

Apple warned investors in January that iPhone sales had taken a hit from an economic slowdown in China. CEO Tim Cook suggested Tuesday that the worst may be over, saying Chinese shoppers had responded to price cuts.

But modest price reductions may not be enough to compete with Chinese smartphone makers like Xiaomi and Huawei.

Huawei shipped 30 million phones in China in the first three months of the year, more than any other company and a 41% increase over the same period in 2018, according to research firm Canalys.

Apple AAPL sales in China in the first quarter plunged by 30% to 6.5 million phones — its worse decline in two years, according to Canalys.