The very first step in this direction is to have a google account. Once you have a google account follow below steps.
To submit your URL to Google, you first have to login to your google account. By this time you are logged into to your google account you will have to browse this link: www.google.com/webmasters/tools/home
This link will open a dashboard where you can see search console option.
You will find a button to the left of the Search Console input field. By default, this is labelled “website.”. Click the button and select the second option from the drop-down menu: Android app. Enter the root URI of your app in the input field:
com.[package name].app (for example: com.testApp.app)
The tool now checks whether you are authorized to manage the app. If so, it automatically confirms the “property” in the search console. You should receive a confirmation e-mail after two days at the latest.
Submit site to Google
There is a new version of Google Search Console you register your website in the left sidebar. Click on the “add property” button. A cursor appears at the same position. As already explained above, enter the entire URL of your domain or webpage there. Then click on the “+ add property” button to submit your indexing request.