Android will now scan sideloaded apps for malware at install time
The Google Play Store might not be perfect for stopping Android malware, but its collection of scanning, app reviews, and developer requirements makes it a lot safer than the wider, unfiltered Internet. The world outside Google's walled garden has no rules at all and offers a countless number of questionable apps available for sideloading. To help combat the surge of sideloaded malware, Google Play can now pop up a malware scanner at install time if it decides the app you're trying to sideload is interesting.
Google Play's malware system, called "Google Play Protect," has always been able to check sideloaded apps for malware, but it used faster techniques like a definition file, and this happened quietly in the background. This new technique will delay your app installation with a full-screen "scanning" interface while Google runs a deep scan of the app code. Google's blog post says this is "real-time scanning at the code-level to combat novel malicious apps" and that Google Play Protect can "recommend a real-time app scan when installing apps that have never been scanned before to help detect emerging threats."