A Chinese app developer apologised on Tuesday after Apple kicked out more than 250 applications that collect personal data in violation of the company's privacy policies from its online store.
The iPhone maker made the announcement a day after researchers discovered hundreds of apps used Chinese advertising software that extracts "personally identifiable user information".
Youmi Mobile Technology "apologised" to developers and partners for the disruption to their business, according to a statement posted on its website.
Researchers at the US mobile analytics firm SourceDNA said Sunday they had discovered hundreds of apps that extract personal information, saying it was "the first time we've seen iOS apps successfully bypass the app review process".
Apple does not allow third-party applications to share data about a user without obtaining users' permission, and it rejects apps that require users to share personal information, such as email addresses or birth dates.
The researchers said they found 256 apps with an estimated one million downloads that have a version of Youmi that violates user privacy.
Youmi denied "collecting personal information (mobile phone numbers, e-mail address, for example) or offering to sell personal information," it said in the statement.
In September, Apple confirmed hundreds of popular mobile apps has be infected with malicious software potentially allowing access to private user data and passwords, including two widely used Chinese apps, instant messaging service WeChat and ride-hailing app Didi Kuaidi.