Cross-Device Identity: Bridging The Mobile App to Mobile Web Divide

You might be reading this blog post on your mobile phone. But that’s not all. Did you check your weather app this morning? How about election coverage?

Deterministic cross-device matching is important for accurate attribution, because the average consumer switches between his or her 4.5 devices regularly, interacting across both apps and mobile websites. The more granular and accurate the user data, the better your attribution partner can follow your users along the path to conversion.

Convertro's 100% deterministic cross-device solution lets you follow your customer’s path across their mobile phones, tablets, and computers as they interact with your brand at work, home, and on the go.  The result is a more accurate, rich understanding of how your media works across multiple devices to influence a customer’s purchase decision, which can help you make smarter investments with your advertising spend.  The breadth of data to which Convertro has access, and the way in which we identify users across devices is why The Forrester Wave™: Marketing Measurement And Optimization Solutions, Q4 2016 gave Convertro the highest possible scores in Data Acquisition, Cross-Channel Identity, and Granularity Resolution.

Based on this report, published last month, we have had a few questions from clients and prospects around our robust cross-device matching capabilities and how we do it. Here, we will focus on the mobile app ad to mobile web connection.

The Situation

The average person uses over 27 apps per month and sees 40+ marketing and non-marketing touchpoints on their way to conversion. Advertisers have greatly shifted budgets to mobile: In 2016 mobile ad spending was projected to account for 60.4% of digital ad spending by eMarketer. 

So users are inevitably seeing a lot of mobile ads within apps they use, and clicking out on some. But  technological limitations and restrictions (eg: cookie blocking) put in place by certain mobile browsers make it difficult to link the ads a user interacts with in a 3rd-party mobile app to actions they take afterward in their mobile web browser; even if on the same device.

Since the mobile app and mobile web browser function as two separate environments and are tracked by different methods, the reconciliation process of identifying users across the entire path to purchase can be tricky. Therefore, without a workaround to circumvent these limitations, it can appear that the in-app activity and the mobile web browser activity were performed by different users.  Without the ability to accurately track a user's transition from an ad in an app to your mobile website, it can be difficult to accurately optimize your mobile media campaigns.

Convertro’s Solution

Fortunately, Convertro has a solution to effectively track this transition and ensure that in-app ads receive proper credit for out-of-app conversions.

  • We insert a redirect between the in-app ad and the mobile web landing page

  • The redirect captures the user’s device ID (IDFA/GAID) from the ad in the 3rd-party app and creates 1st-party and 3rd-party cookies for the mobile web browser that contain a unique Convertro ID for the user

  • This establishes the Convertro cookie as a "trusted” 3rd party cookie in the mobile web browser, which ensures they are not blocked by iOS Safari browsers.

  • We now can link the click trail based on the user's device ID to the click trail tracked with the Convertro cookie ID in the browser

  • The advertising device ID (IDFA/GAID) and the Convertro browser cookie are linked together and added to Convertro's co-op cross-device pool

Don't worry; our Marketing Tag Builder does all the work for you. The steps are outlined in our newly revamped Knowledge Base.  Got questions? If you are not an existing client, please contact us at

Additional notes:

The opt-in shared or co-op device pool contains device links from all participating Convertro clients. This gives participating clients access to a massive, combined collection of deterministic cross-device links, which also includes linked device data from AOL, Verizon, and Millennial Media.

Alternatively, clients can store their device links in a private device pool managed by Convertro. Private device pools contain only the device links created from clients' own customer data and are not enhanced with device data from AOL, Verizon, and Millennial Media.

This solution respects the user's "Limit Ad Tracking" preference set in the device's privacy settings, as received from the publisher. If set to "true", Convertro does not track the device ID and instead creates a random Convertro user ID.

Sources: Convertro data, Measurement Is A Digital Buyer's Best Friend", Forrester Research, Inc. 2016 and Nielsen, Q4 2015

This post was written by Maryam Motamedi, Senior Product Marketing Manager.