Recently, China threatens to require every app to have a license in order to go on sale, as reported by New York times. The time is too coincidental as Apple adopted https on iTunes for searching and downloading Apps.
Before this adoption, searching for certain keywords such as "vpn" would lead to a connection reset on iTunes and visiting the page for certain Apps, such as VPN Express would also cause a reset, which means there is no way for users in China to search for or download certain Apps even if they are available in China App Store.
But because now https is implemented by Apple on almost all connection to iTunes server, Great Firewall of China has no way to selectively block connection to certain contents. A test to the same link mentioned above with https protocol yields no censorship.
This change provides a commercial platform in China(China App Store uses CNY for payment) not subject to the arbitrary censorship of the government. For example, opendoor an app dedicated to circumventing the Internet is on sale on China App Store and users are willing to pay to remove ads in the app. Any other trading platform, such as Taobao(Chinese version of ebay) is actively censoring Internet Circumvention tools and selling anti-censorship tools there is not possible.
Therefore, it is highly likely that the government have noticed this loophole in its censorship net, and is now trying to close it.