The apps were frequently pitched as employee and parental monitoring tools, but CNET found that some people weren't using the app that way. Reviews for Spy Tracker, for instance, included numerous people using the app to stalk romantic partners. The clients were mildly popular -- they had 130,000 total downloads.

When asked for comment, Google confirmed to Engadget that it pulled the apps. The company already has policies forbidding these apps and has taken some steps to fight partner abuse, such as donating resources to anti-domestic violence charities like Refuge and working with privacy and security researchers. It also published a study in 2017 to guide privacy and security practices when dealing with abusers.

The app report is a not-so-subtle plug for Avast's stalking app detection tools, but it also illustrates the challenges Google faces in keeping these kinds of apps out of its catalog. These apps can clear the Play Store's automated app screening even though they're designed with malicious intent, and they might not be reported until after they've had an opportunity to do some damage.