In the fourth quarter, production of iPhones faced disruption as a key factory grappled with strict health-crisis restrictions that fueled discontent among workers over conditions at the factory.

Staff also protested over pay.

But on Thursday (January 5) Foxconn said that output at the factory in China had returned to normal, and that December sales were better than it expected.

The company said revenue for 2022 rose almost 10.5% from the previous year to a record high, driven by growth across major product lines from smartphones to servers.

Analysts say Foxconn assembles around 70% of iPhones, and the Zhengzhou plant produces the majority of its premium models, including the iPhone 14 Pro.

A company source told Reuters last month it aimed for the plant to resume full production around late December-to-early January.

Foxconn shares closed down 0.1%, below the broader market which ended up over 0.7%.