In 2016, Google’s App Indexing and how Google handles ranking apps will be an incredibly important area for SEOs to pay attention to. We had the opportunity to talk with Rajan Patel, Google’s director of mobile search, to discuss the key differentiators between how Google ranks web content versus app content. Now that Google ranks app-only content apps in the mobile search results, we need to understand how ranking differs.

The key here is that Google seems to be depending a lot on their App Indexing API and the signals they get from that API.

App Indexing API Replaces Google PageRank For Ranking Apps

Rajan Patel tells me that with apps — and especially app-only content — Google doesn’t have some basic ranking signals they have with web ranking. Specifically, Google doesn’t have links, anchors and PageRank signals when it comes to ranking apps. Google needs to find a set of signals that can replace the signals they are losing for app ranking. PageRank is mostly about figuring out the authority of a web page, so how does Google determine the authority of a deep link within an app? Rajan Patel says they get some of that data from the Google App Indexing API. “We do use the App Indexing API to help us rank app content,” Rajan told us.

We covered before that Google does give apps a ranking boost for using the App Indexing API, but this goes beyond that.

Measuring Time Spent In Specific Sections Of Your App

The Google App Indexing API not only lets app developers communicate the title and option description of the content pieces within app, but it also shares how long app users spend on each section or page within your app.

In the app indexing API, the developer has to send a start and end time for each action or fragment. They look like this:

AppIndex.AppIndexApi. start (client, viewAction)

(client, viewAction) AppIndex.AppIndexApi.end(client, viewAction)

This tells Google how long users spend on a specific view or action within the app. Although Google did not communicate how reliable that is as a ranking signal, one has to assume the number of users and frequency of those actions can influence how Google determines how authoritative and important a specific section or action fragment within the app is. Of course, it seems fairly easy to spoof, but Google is also outstanding at spam detection.

Google’s App Crawler

Rajan also explained that Google has an app crawler that crawls under the normal user agent of GoogleBot. It also can crawl your apps content the way it would crawl your web content, and it can understand the URIs and content within those sections of your app. The App Indexing API is a fundamental core to help Google get this content, but it is possible Google can use this crawler to detect more content within apps, as well as find potential spam or cloaking cases.

I asked about spamming or cloaking titles of articles, where you communicate one title which does not match the actual title of the content within the app. Rajan Patel said Google “aggressively monitors and penalizes” that type of behavior. It is unclear if Google has run into these attempts yet in the app world, but you must believe they are prepared for it.

In the Google Search Console, Google is able to show in the Fetch and Render for apps a picture of how GoogleBot sees your content within your app. Here is a screen shot of the Search Engine Roundtable Android App,as seen by GoogleBot:

As you can see, Google is clearly indexing the content within a specific section/article within the app.

iOS vs Android Apps

Google undoubtably has more access and capability to get into the content of Android apps than they do iOS apps. If anything, the app streaming feature Google announced yesterday proves that. Further evidence is the fact that the Google Search Console fetch and render feature only works for Android apps.

But Google’s App Indexing API can be directly integrated with your iOS apps. Since the App Indexing API works with iOS apps, iOS developers should make sure to add that to their apps. I doubt GoogleBot has much access into iOS apps, but that is where the App Indexing API comes in. iOS developers can communicate what their app and app sections are about to Google through the API. Google will have to rely more heavily on the API for iOS apps versus Android apps, although one wouldn’t think Google would bake in a bias for Android apps over iOS apps into their ranking algorithm.

App Indexing API Is The SEO App Key

In short, if you are getting into the app world and want to rank well in Google — you must deploy Google’s App Indexing API within your app, and of course, build a great user experience for your app users.