How to Publish an App on Google Play Store for Free?
To publish an app in Google Play store, you need to create an account in Google Play Developer Console which will cost you 25 $ (USD).
The reason behind the fees is to keep out the fake, duplicate accounts and hence keep out unnecessary and worst apps flooding the playstore.
Once you pay the initial fees, you have a fully functional Google Play Developer Account through which you can publish as many apps as you want (free/monetized).
I would recommend you to pay the initial fees because you can easily earn that amount by monetizing your apps or by keeping ads in your app via ad-revenue or admob.
Method to publish an app on Google Play Store for free?
Nothing is free in this word :)
But you have many other option to publish your app in other app store which is not very famous but they have big user base.
For Google play you need to pay one time registration fees of $25, After that you can publish as many application you want.
You can check my app which is publish both on play store and app store
Another Way to publish an app on Google Play Store for free?
There is a minimum submission payment of $15, so you need to pay to represent your app in Google App.
Sure you can get in touch with the Google Play moderators and ask to be published/registered for free and give the reasons why you refuse to pay.
Believe me that the $15 is not much as the app owners spend even millions to promote their app and make it visible for Store users. E.g. They can boost motivated traffic to increase app position and need to pay in order to get the highest spot in ranking.
Note:- This Article on How to Publish an App on Play Store is Only Meant to Provide Information.