Facebook and Google have reached an agreement that will let Android users hop from search results indexed by Google directly to the Facebook app.
Google parent Alphabet told The Wall Street Journal that Facebook allowed it to "crawl and index" the social network's app. For now the "agreement" appears to be limited to Android devices, and will mean that some content from Facebook will appear as so-called 'deep links'.
The agreement doesn't involve Google in searching and indexing any more information than it already does on the web version of Facebook.
But it does mean Facebook has implemented Google's App Indexing service, which acts as a bridge between search on the web and apps and is one component of Google's efforts to keep search relevant on mobile.
App Indexing caters to apps that have corresponding content to a web page. It currently doesn't support apps that don't have a web page. Apps that implement the service are indexed by Google and will appear in results when people search the web on a mobile browser.
Users are returned deep links that lead to relevant content in an app rather than a mobile webpage.
As Google explained when it launched the service globally last year: "Whether you're searching for a movie, an apartment, restaurant, shoes, news article, book, recipe, or even a job, you can now go directly to the relevant content within apps that you've installed on your phone."
It launched with support from 24 apps including Pinterest, TripAdvisor and Zagat, but Google is encouraging more developers to follow suit.
The attraction for developers at least on Android is that users will see an install button on search results if a user has searched for content related to the app, helping overcome the app-discovery challenge.
Google brought app indexing to iOS 9 in October, which displays an install button in Google search results on Safari that lead users directly to Apple's App Store.
Clearly Facebook doesn't have that problem, but the move was characterised by the WSJ as a win-win for the two biggest players in online advertising, which are both vying for supremacy in mobile advertising.
"When people search for public Facebook content on the mobile web, those who use Facebook for Android can now click through and go straight to the Facebook app," a Facebook spokeswoman told the WSJ.