"The plugin forcibly displays ads on the user's lock screen, triggers video and audio advertisements even while the phone is asleep, and displays out-of-app ads that interfere with a user's interaction with other applications on their device," said Lookout.
According to Lookout, this adware also prevented some users from performing tasks as basic as answering a call. However, these issues did not show themselves immediately, instead starting to become visible after at least 24 hours of the app being installed.
All apps that contained this adware were released on the Play store by the same publisher, CooTek, which is a Chinese mobile Internet company listed on the New York Stock Exchange.
Perhaps the most well-known app affected by BeiTaAd was TouchPal, a popular keyboard app.
Lookout reported BeiTaAd to Google and it has since been removed from all affected apps on the Google Play Store.