The Clock application is seen on an Apple iPhone in this photo illustration on January 29, 2019.

Apple has threatened to remove applications from the App Store if they record users' actions without their explicit permission.

Earlier this week, TechCrunch reported that iPhone apps from Expedia, Air Canada and Hollister were using "session replay" software from a company named Glassbox that allowed them to record a user's actions, such as screen taps and swipes, while using an application. The applications did not tell users that it was recording their actions inside the app, according to the report.

Apple has since put developers on notice that they need to tell users if and when they're recording a user while they're using an app.

"Protecting user privacy is paramount in the Apple ecosystem," Apple said, according to TechCrunch. "Our App Store Review Guidelines require that apps request explicit user consent and provide a clear visual indication when recording, logging, or otherwise making a record of user activity. We have notified the developers that are in violation of these strict privacy terms and guidelines, and will take immediate action if necessary."

One developer told TechCrunch that action includes removing their app from the App Store if it isn't updated to meet the guidelines.