Google recently made an announcement that will benefit mobile app developers and app users: They’ve started indexing app content.

The new app indexing feature allows Googlebot to crawl and index content within Android apps. Webmasters can specify which content they want Google to index through their existing Sitemap files and Google Webmaster Tools.

When both the webpage and app content are indexed successfully, users who have the app installed will see deep links to the content right in the search results. This preview from the Google Webmaster Central Blog shows how deep links to app content will appear and function once they’re implemented:

Clicking on the “Open in app” button will launch the app and take the user to the content directly.
Google says they’re currently testing this new feature with a group of app developers. Users signed in on their Android devices in the US will see deep links for these developers’ applications in Google search results pages.
Google wants to implement this functionality to more websites and apps “in the near future”. They’re encouraging developers who are interested in enabling indexing for their apps to get started in three simple steps:

1. Fill out this form to express interest in app indexing.

2. Configure both the website and the app to enable indexing by following the steps listed in this page.

3. Provide information about alternate app URLs through a link element on the website’s pages, or the Sitemaps file.

The app indexing features are only available for Android apps for now, and Google has not mentioned anything about making it available for Windows or iOS apps yet.