I downloaded the Tor browser app. through Google play, is the app. safe and anonymous even though it's downloaded through Google?
If you ever have questions about what is legitimately Tor, check out https://torproject.org. This is the team that actually makes the Tor browser ad the Tor network itself. Here is the page for android. You can make sure that you are getting the real Tor Browser and not malware.
The Tor developers stand by their work on Android the same as any other operating system. Of course, it is up to you to know how to keep yourself anonymous online. Software can only do so much.