No platform is a 100% safe. No matter how good the team behind it is doing, there are always the chance that malicious things go unnoticed.
Google operates Android and its official app store, the Google Play Store. The company said that it has removed "nearly 600" apps from the store, banning them from monetizing ads through Google AdMob and Google Ad Manager.
That because they have violated its disruptive ads policy and disallowed interstitial policy.
According to Google on its blog post:
Google said that "disruptive" means that the ads are displayed to users in "unexpected ways".
The company said that it also defines disruptive ads as those that include "impairing or interfering with the usability of device functions."
"While they can occur in-app, one form of disruptive ads we’ve seen on the rise is something we call out-of-context ads, which is when malicious developers serve ads on a mobile device when the user is not actually active in their app."
The makers of the apps may have intended to make the ads intrusive, hoping that users will click on the ads more often, or sometimes unintentionally.
Worse, this kind of ads wastes advertiser spend.
Google continued by saying that:
While Google also said that it is investing on new technologies to better detect and prevent emerging threats, Google is still often seen less secure than Apple.
This is because Apple leverages a more stringent app reviewing process, and is known to frequently deny new apps and updates.
For Google, 600 apps is indeed many. But if counting the whole Android ecosystem, Google Play Store has at least 3 million apps.
What this means, Google has a lot to do.