Both Ad SDKs were found in an abundance of apps in Google Play. Adware.Cootek infects over 2,000 Play store apps alone, according to our Mobile Intelligence System. Both pieces of adware have remarkably similar traits, displaying full screen ads inside and outside of the infected running app. Malwarebytes for Android warns you when Ads are crossing the line. Its fully up to you, the user, whether to delete the offending app or ignore our warnings. Use common sense when selecting an Ad SDK.”]
Source: https://blog.malwarebytes.com/cybercrime/2017/10/yet-more-mobile-adware-found-in-google-play/