Google App Indexing - How To Code, Please?

Dear all,

Google offers the possibility for app indexing. There is to code in my opinion an activity starter with an intent. The app indexing has the advantage, that the app appears in the search results of the Google search engine, because Google is able to crawl it. Does someone of you know how to code it, please?

Update: I have found something here

Here I found another useful information

Thank you!

Martina