From blog.avast.com
Avast researchers have discovered a large campaign of HiddenAds on the Google Play Store. HiddenAds refers to a family of Trojans that disguise as safe and useful applications, but in fact only serve to display intrusive ads to the user. The discovered apps mask as games and have a timer-triggered hide app icon feature alongside the ability to display device-wide ads. The apps have over 15 million combined downloads on the Play Store.