Hon Hai Precision Industry Co. reported an unexpected rise in quarterly earnings after the main assembler of Apple Inc.'s devices rode record iPhone sales during the pivotal holiday shopping period.

The world's biggest contract manufacturer of electronics reported a 30 percent increase in net income to 68.8 billion Taiwan dollars ($2.3 billion) in the three months ended December, according to Bloomberg calculations derived from previously released data. That surpasses the NT$48.8 billion average of analysts' estimates.

Hon Hai, better known as Foxconn Technology Group, derives about half its sales from Apple, data compiled by Bloomberg shows. The world's most valuable company shipped an unprecedented 78.3 million iPhones during the October-December quarter, despite its latest device representing a modest update on its predecessor. Optimism around Apple's iPhone for 2017 — the 10th anniversary of the iconic device — has driven the Taiwanese company's stock close to a decade high.