Way back when Android 4.2 Jelly Bean was released, Google added a feature called Verify Apps that sought to protect users who inadvertently may have downloaded a piece of malware and attempted to side-load it onto their phone. The service, which is enabled by default on all Android devices, scans apps that are installed from sources other than the Play Store, and warns the user if they may be potentially harmful.
It’s so silent and unobtrusive, most users don’t even know Verify Apps is running, which also means they don’t know when it’s not running. As Google explains in a blog post, that could be the result of an app that has snuck by its gate-keeping and purposefully turned it off, opening the door for potential problems. Google calls these devices Dead or Insecure (DOI), and in turn, if an app has a high percentage of DOI devices downloading it, it will be considered a DOI app. That’s where Google’s security wizardry comes into play.
Read more here:: IT news – Security