Anonymous vote on Play Store I often would like to vote app on Play Store, but I do not want to shows to my contacts my votes or the app I installed on my device.

How can I do that?
There is a similar question posted on Google product forums,
Forced to join google + in order to rate apps?
Answer: It's not possible to anonymously rate or review an app. And letting users post anonymously will result in simply posting a review in anger, in an attempt to hurt the developer or app. Making someone identify who they are, in this instance, ensures that they are more likely to think about what they are writing, and if they're going to criticize, they are more likely to do it constructively. Also read this Google product forum post,

It sounds like the heart of your concern is you want to be able to
leave reviews anonymously and the recent change won't allow for that.
Requiring accounts to write reviews is increasingly common (Yelp,
TripAdvisor, OpenTable, and others). In the world of mobile, Apple
requires sign-in with an AppleID to review apps and other content.  In
fact, requiring sign-in has become so prevalent that there's already
industry research on it (example here).
Unfortunately, for folks who don't want to sign-in to leave reviews
like yourself, this shift isn't a desirable one.  Changes like this
can be frustrating if it's not what you want to happen and I'm sorry
that you're so frustrated by it.  Aside from illuminating that this is
a greater trend, there's unfortunately not any other solution except
that I hope that you can make the choice that's right for you.
Finally, I'm not sure what your objective is with leaving a review for
the app and don't know if this will be helpful to you, but know that
you can reach out directly to the app's developer via these steps.

Go to Google Play and select the app in question.
On the app's description page, scroll down to the &quot;Developer&quot; section.
An email address, a phone number or a website will be provided.