A report says hundreds of Android games are quietly tracking users' TV habits by turning on the microphone.

While this is already a known practice among mobile apps, some of them fail to disclose this process, or are not clear about their motive, according to The New York Times.

It is said that once these applications are downloaded to the mobile phone, they are easily able to monitor viewing habits, even when the games are not being played, as long as the apps are running in the background.

The act is possible by using a software from the start-up Alphonso, which collects TV viewing data for advertisers. Through audio signals acquired from the mobile's microphone, the software is able to identify the shows and commercials viewed by the user, and sometimes, even the places they visit or the movies they see.

The report adds that tracking occurs even in games that otherwise do not require the use of the mic.

By doing such, Alphonso is able to analyze what TV ads may have prompted customers to visit a certain store, or buy specific equipment.

Alphonso chief executive Ashish Chordia said that roughly 1000 games, messaging, and social media apps are using their software, but with the consent of the users. "The consumer is opting in knowingly and can opt out any time," he said.

Alphonso added that their access to users' microphones and locations is specified in the app descriptions, saying that this is in full compliance with the guidelines from the Federal Trade Commission.

But The Verge notes that these applications could give more explanation about their intent.

For instance, the media outlet tried downloading a game called "Endless 9*9 puzzle," which did ask for access to microphone and location, but did not immediately specify what it is for.

While Alphonso refused to name the applications using their software, The New York Times, upon digging, found that some 250 of them are available on the Google Play store, among which are apps and games directed for children, like "Teeth Fixed," "Zap Balloons," and "Honey Quest." Alphonso, however, denies that they approved their software to be used by applications meant for kids.