Chinese developers make almost a quarter of global App Store earnings, says Tim Cook

Tim Cook made a trip to China for the country's World Internet Conference and gave a surprise keynote address, where he brought good news for app developers: They're making a ton of money.

Cook told the audience that 1.8 million Chinese developers have made around $16.93 million on the App Store, according to Reuters. Thats about a quarter of the $70 billion in total revenue developers have earned since the digital marketplace launched in 2008, a stat Apple trumpeted earlier this year ahead of its annual WWDC conference.

China is essential to Apple's global success, as the country offers a huge opportunity as the world's largest smartphone market. The country passed the US to become the biggest spender on apps in 2016, so the proportion of App Store earnings shouldn't come as a big surprise.

Apple manufactures its products in China but faces stiff competition from domestic companies like Huawei, Xiaomi, and Oppo, which offer less expensive smartphones that are popular with the growing user base.

Cook's appearance marked the first time he attended the conference, and Google's Sundar Pichai also attended to take part in a panel on the digital economy, according to Bloomberg.

The CEOs' presence at the event didn't come without controversy, however. The conference was hosted by the Cybersecurity Administration of China (CAC), the government body that dictates the country's strict internet regulation and policy. Apple was also criticized for complying with Chinese law to remove several VPN apps from the Chinese App Store earlier this year.