Apple reportedly issued warnings to Chinese app developers over attempts to develop a system to protect their advertising revenue from beefier privacy protections included in a forthcoming iOS update.
Financial Times (FT) wrote the company contacted at least two China-based developers deemed to be collecting information which could identify a user and their device, calling them on to cease the practice.
The newspaper said one of the developers employed a China Advertising Association tool named CAID to identify and track users.
Apple reportedly called for the developer to update its app to meet App Store regulations within 14 days.
FT also reported Apple found the tracking feature in the SDKs of big-names including ByteDance, Baidu and Tencent, though noted the US company did not publicly disclose this.
Apple faced a backlash from advertisers over plans to restrict the data apps can collect when it launches iOS 14: this caused it to delay the launch of the platform, though the changes are expected to come into force during H1.