In comparison to Apple, Google previously relied on automatic review processes in order to cope with the massive number of apps submitted every day, so that interested people could use
new apps immediately.
Now Google is changing this manubrium, because a lot of malicious, exploitative, inappropriate, and low-quality apps made it through, affecting the user experience and creating trouble for developers and users.
Besides it is an advantage for the developer, too: on the one hand a certain quality standard can be preserved and on the other hand the developer is able to see the app’s publication status in more detail, and learn quickly if and why an app has been rejected or suspended.
Although the apps are reviewed manually, it doesn´t cause any delay. The reason why Google’s app review team is able to process app submissions so quickly is because the system also includes an automated element. Before app reviewers are presented with the applications, Google uses software to pre-analyze the app.