Apple's stock closed down 4% on Thursday, its worst day since August 5th, following reports of weak iPhone sales in China.The stock price has fallen nearly 12% from its December peak, making it the worst-performing of the seven largest technology stocks in 2025 so far.A report from Canalys suggested that Apple had fallen to third place in terms of smartphones sold in China in 2024, behind Vivo and Huawei.Apple shipped 15% of the 284 million phones sold in China last year, down 17% on an annual basis.