The feature lets Google deliver in-app content in search results on Android devices that have the apps installed. For example, if you have the Wikipedia app installed on your phone, and get a Wikipedia search result, the result can be opened in the app right from the search results page.
Last week, Google announced support for a slew of new apps, and opened up the ability for any developer to participate in app indexing.
They held a session at Google I/O called "The Future of Apps and Search," which discussed bringing search and apps together to give users a better experience. If you're interested in participating in app indexing (which you probably should be if you have apps), you better give it a watch. Google posted the video online over the weekend.
Google also announced that app result title links will start taking users directly to the content inside the app when it's installed. It still provides a link to open the content on the website.
Google also started clustering app results together in search results globally. This is a feature that was available in the U.S. back in December.
Image via Google