Apple may have skirted the slowing smartphone market to become the U.S.’s first trillion-dollar company. Elsewhere, investors are rapidly recalibrating their view of the industry’s outlook.
Shares in Sunny Optical, a Hong Kong-listed firm which makes smartphone cameras and lenses for the likes of China’s Huawei, plunged 24% Tuesday, wiping out $4 billion of market value. The catalyst was Sunny’s poor first-half earnings, particularly the first year-over-year decline in the company’s gross profit margin since 2014. Sunny blamed...