Tim Cook, Apple’s Chief Executive Officer, took an unusual step reassuring shareholders on Monday about its business in China. The statement came ahead of a 13% drop and rebound in stock of the iPhone maker.

Sudden drop in the Chinese stock market and Beijing’s recent devaluation of yuan have shaken Apple investors that were already worried about slowing growth in the world’s No. 2 economy.

Cook took a daring step by commenting on Apple’s business health midway through a financial quarter. Before the opening bell on Wall Street, Cook sent his response in an email saying that iPhone activations in China had accelerated over the past few weeks.

Cook also said that the App Store in China have had its best performance so far in the year in the past two weeks. “Obviously I can’t predict the future, but our performance so far this quarter is reassuring. Additionally, I continue to believe China represents an unprecedented opportunity over the long term”, Cook wrote.

As per reports, in the early minutes of trade, Apple shares saw a fall of as much as 13% to a year-low of $92. But almost after two hours, they reversed those losses to trade up 2.25 % at $108.12, adding around $85 billion to Apple’s market capitalization from its earlier low.

FBR analyst Daniel Ives said that the statement released by Cook publicly gave some positive signs about what Apple is seeing out of China during this market meltdown. It provided a relief to investors who have nightmares about what China can become over the coming years for Apple.