Identity Resolution Demystified: What is Cross Device ID?

Americans continue to become more connected than ever, spending an average of six hours a day on the internet. That’s great for brands looking to market to them online — as long as they have the technology to provide people-based marketing campaigns.

Consumers are reading, shopping and engaging online via multiple devices a day, from smartphones and tablets to desktops and even their connected TVs. When you multiply out the number of devices each user has by the 4.66 billion active internet users in the world, we’d say that’s a pretty large number.

To create cohesive messaging for a single consumer no matter what device they’re on, you’ll need the technology to bring all of that information together. And that’s where cross-device identification comes in.

Cross-device identification is the science of combining information from different customer activities across devices to generate a unified, single customer view.

How is it different from an identity graph?

The definition might sound similar to what we covered in our post on identity graphs, but here’s a simple way to understand the difference between the graph and cross-device ID:

The identity graph is the actual database where all of the information is stored for later use. The cross-device is the most important underlying technology that powers that database.

OK, but what does that really mean? Think about it this way: If a user reads an article on their phone when they wake up, shops on their tablet at lunch time and then makes a purchase from a different site that night on their desktop, cross device is the technology that connects all of the dots between those actions and devices.

Why is cross-device ID important?

Without cross-device ID, brands would only be able to reach consumers with an ad on each of those specific devices. For example, you’d only be able to show an ad for the site they shopped on at lunch on their tablet since that’s the one they viewed it on. But with cross-device ID, all of that information is merged together from those devices to a single profile. You can connect what they read, viewed, and purchased to create a targeted campaign with that data.

And that, my friends, is how you do people-based marketing.

You can then create and send targeted content or advertising to consumers across multiple platforms and devices. That allows you to reach your audience when and where they are ready to engage with your brand. 

If those benefits weren’t enough, cross-device identification also helps you understand your audience’s habits across devices, giving you the data you need to build a complete cross-channel profile of them. The more data you have on them, the better you can target your campaigns.

How does it work?

What you’re trying to find out with cross-device ID is basically if smartphone A belongs to the same person who uses tablet B and laptop C. There are two ways to do that and identify the consumer:

  1. Deterministic identification links PII (personally identifiable information) to a device, like with an email or social media login. This option is more accurate but limited by scale. Really, only online giants like Facebook, Amazon, and Google have the capabilities, data, and scale to create a graph with any real effectiveness or reach.
  2. Probabilistic identification uses math, algorithms, and anonymous identifiers to infer a connection between devices and people. Unlike the first option, this one is infinitely scalable but less accurate — though still about 95 percent correct and allows you to reach nearly the entire internet. It gives you more control and flexibility and is especially ideal for behavioral targeting. Those same online giants (Facebook, Amazon, and Google) focus their efforts on this strategy because it’s what gets them additional, incremental reach.

Great, but what can cross-device ID help me do?

The main benefit of using cross-device identification is that it allows you to amplify your audience. You can go beyond the first-party cookie you set on your user to advertise, and you can instead reach them wherever they are. Pretty big deal, right?

The biggest use case for cross device ID is retargeting, followed by sequential messaging, universal frequency capping (to prevent hitting people with too many of the same ads on any number of devices), and location extension (marketing to people as they near a specific location). 

Just be sure that no matter how you use the technology, you continue to provide a unified brand experience that flows from one device from another. Consumers should only see your brand, instead of the device or channel you use to deliver the messaging. Basically, don’t let them see what’s going on behind the curtain. They should be able to sit back and enjoy what you show them.

Cross-device identification is a powerful, scalable technology that’s at the heart of identity resolution.

What’s next?

All marketers want a clearer picture of who the consumer is behind the device to better reach them with targeted campaigns.

Achieving this level of tracking can feel like a challenge because consumers are constantly moving from one device to the next throughout their purchasing journey. But with the launch of various user IDs, we’re moving closer to solving this problem — and maybe even solving the problem of research online, purchase offline (ROPO), too.

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