Researchers found 85 Google Play apps with more than 8 million downloads that forced users to view fullscreen ads.
The apps, which posed as photography and gaming programs, contained a family of adware that was highly disruptive to end users. Once installed, the apps displayed ads in full screen—a setting that forced users to view the entire duration of an ad before being able to close the window or get back to the app. The apps showed an ad every five minutes, but the people operating the platform had the ability to remotely change the frequency.
AndroidOS_Hidenad.HRXH, as the adware is called, used several tricks to evade detection and removal. A half-hour after being installed, for instance, an app would hide its icon and create a shortcut on the device home screen. (That's according to a write-up from Trend Micro, the security firm that found the apps.) Hiding the icon prevented the apps from being uninstalled by dragging and dropping the icon uninstall section of the device screen. Android 8 and later versions require user confirmation before an app can create a shortcut, but even if users of these versions didn't agree, the icon would nonetheless remain hidden.