Customers often transition seamlessly between devices throughout their purchasing journeys, making it essential to understand these cross-device interactions. Cross-device tracking offers invaluable insights into user behaviour, allowing you to harness this data to craft personalized marketing campaigns and improve conversions.

Cross-device tracking presents its own challenges and benefits. This article explores the best practices that will help your marketing team use cross-device tracking ethically and effectively.

What is cross-device tracking?

Cross-device tracking is a technique that allows businesses to track user activity across different devices and platforms to target users with relevant, personalized marketing. It involves correlating activity to identify multiple devices belonging to the same user, ensuring consistent content delivery across all devices.

How does cross-device tracking work?

There are two main methods for cross-device tracking. 

  • Deterministic method: This method tracks online behaviour by collecting evidence that a single person uses multiple devices. It relies on user data, such as login information and in-app purchases. For example, users often use the same passwords and payment methods across all their devices.
  • Probabilistic method: This method uses patterns and algorithms to identify users across different devices. It makes educated guesses based on factors like IP addresses, operating systems, device types, and cookies. This method can be a suitable substitute if direct data is unavailable.

Deterministic tracking is more reliable but requires extensive databases, which is why it is typically used by large organizations like Google and Facebook. The probabilistic method is less costly but relies on inferences rather than certainty.

Combining both deterministic and probabilistic data allows you to create an ID graph—a database that maps the connections between devices used by a single person. This approach pairs various identifiers to build a comprehensive view of device usage.

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How does cross-device tracking help marketing?

Holistic view of customer behaviour and preferences

Cross-device tracking allows you to compile a comprehensive view of your customers’ interactions across different platforms and devices, from smartphones and tablets to desktops. With this data, your marketing team can gain deeper insights into user preferences and behaviours.

These insights can be further enhanced using machine learning (ML) models—algorithms and statistical methods that enable systems to learn and improve from experience without being explicitly programmed. This allows for more accurate identification of patterns and trends in customer data.

Precise audience segmentation for targeted campaigns

With this holistic view of user behaviour, you can segment your customers more accurately based on their interactions across devices. This precise segmentation involves analysing data points such as the types of devices used or time spent on different platforms.

Understanding these behaviours helps you identify distinct user groups with similar characteristics and preferences. For example, a fashion retailer can segment its audience into groups such as frequent mobile shoppers or desktop users who prefer browsing but purchase in-store. Each segment can then be targeted with tailored marketing campaigns designed to resonate with their specific behaviours and preferences.

User behavior analysis across various touchpoints 

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Cross-device tracking also reveals how users interact with brands at different touchpoints. These touchpoints might include:

  • Browsing products on a mobile app
  • Researching reviews on a desktop browser
  • Receiving promotional emails
  • Engaging with social media posts
  • Completing purchases in-store or online

Analysing and marketing to customers based on these touchpoints provides insights into the customer journey, from initial awareness of your brand to the final purchase. Understanding these interactions helps marketers identify key moments that influence purchasing decisions, allowing for the optimization of marketing strategies.

Enhances campaign relevance and effectiveness

Leveraging cross-device data also helps ensure your campaigns are relevant to users, regardless of the device they use.

This relevance enhances the effectiveness of your digital marketing efforts, as users are more likely to engage with content that aligns with their current needs. Whether a customer is browsing social media on their smartphone or researching products on their laptop, timely and relevant marketing messages improve their experience and increase the likelihood of conversion.

Facilitates conversion attribution to appropriate touchpoints

Accurate conversion attribution is a major challenge in multi-device environments, given the fragmented user journeys across multiple touchpoints.

Cross-device tracking helps attribute conversions to the appropriate touchpoints, such as when a user initially interacts with a campaign on their mobile device and completes the purchase on a desktop. This attribution ultimately helps you understand which channels and strategies drive conversions.

Crafts a seamless and convenient buying experience

A seamless and convenient buying experience across devices is crucial for customer satisfaction and loyalty. Cross-device tracking allows you to provide consistent messaging and user experiences, reducing friction in the customer journey and encouraging repeat purchases.

For instance, a user might browse your website on their laptop and add items to their cart, then complete the purchase later on their phone. As long as your site is optimised for mobile, they will see the same layout and options, making it easy to revisit their cart or continue shopping.

Best practices for marketing cross-device tracking

Clear disclosure of cross-device tracking

Transparency is crucial when implementing cross-device tracking. Ensure your privacy policy clearly explains how cross-device tracking works, including what data is collected and how it is used. This transparency builds customer trust and ensures compliance with legal requirements.

Tip: Include a dedicated section in your privacy policy to disclose the cross-device tracking process. This can help users better understand how their data is being tracked and make the information more accessible.

Provide clear opt-in/opt-out options

Respecting user privacy means offering clear opt-in and opt-out options for cross-device tracking. Allow customers to make informed choices about their data and provide simple mechanisms to manage their preferences. They should also have the ability to change their minds and opt out at any time.

Tip: Implement a pop-up notification or banner that informs users about cross-device tracking and provides immediate access to opt-in or opt-out options. Make sure this feature is visible during the user’s first interaction with your website or app.

Offer accessible options for user preferences

Make it easy for users to manage their tracking preferences at any time. This could include user-friendly dashboards or settings within your app or website where users can adjust their privacy and tracking preferences.

Tip: Design a dedicated “Privacy Settings” section in your app or website’s main menu. Ensure it is easy to find from the homepage and easy to navigate, allowing users to update their tracking preferences effortlessly.

Collect only necessary data

It’s important that you limit data collection to what’s essential. Avoid gathering excessive or irrelevant information to minimize privacy risks and maintain user trust. For example, if you track a user’s searches on their phone, ensure you are only recording searches relevant to your product.

Tip: Conduct a thorough review of your data collection practices and revise your tracking mechanisms to focus solely on capturing information that directly contributes to improving user experience and marketing.

Anonymize or aggregate data


Enhance privacy by anonymizing or aggregating data wherever possible. This helps protect individual user identities while still providing valuable insights for your marketing team.

Tip: Implement hashing or tokenization techniques to anonymise user data before storage and analysis. This ensures that individual identities remain protected while allowing you to analyze trends and patterns in aggregated data sets.

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Implement strong security

Protecting user data is paramount. Implement robust security measures, such as encryption and secure data storage, to safeguard customer information from breaches and unauthorized access.

Tip: Conduct regular security audits and penetration testing to identify vulnerabilities in your systems. Educate your team on best practices for data security and ensure that all staff members adhere to stringent security protocols.

Combine deterministic and probabilistic methods

Using a combination of deterministic and probabilistic methods for cross-device tracking can improve accuracy and coverage. A hybrid approach provides a more comprehensive understanding of your audience.

Tip: Regularly evaluate the performance of each method and adjust your tracking strategy to continually improve accuracy and effectiveness. For instance, as more users create accounts on your website, deterministic methods may become more productive.

Ensure accurate data matching

Accurate data matching is essential to avoid misidentifying users across devices. Consider using eCommerce AI and rigorous data validation processes to ensure the information collected from different devices corresponds correctly to the same user.

Tip: Use cross-device identifiers, such as hashed email addresses or unique user IDs, to facilitate accurate data matching across platforms and devices. Employ advanced matching algorithms that consider multiple data points (e.g., IP addresses and device attributes) to confirm user identities accurately without compromising privacy.

Select effective solutions

Choosing cross-device tracking solutions that are compatible with a wide range of devices and operating systems ensures better coverage and more accurate tracking. Prioritize cross-device tracking platforms that offer SDKs (Software Development Kits) or APIs capable of seamlessly integrating with different devices and systems.

Tip: Collaborate closely with your IT and development teams to assess the scalability and performance of each solution. Ensure that any system or API used meets your specific tracking needs while maintaining data security.

Train your team on responsible tracking

Cross-device tracking is more than just the software you use—it requires education on ethical and responsible practices. Regularly train your marketing and IT teams on privacy laws and data security best practices.

Tip: In regular workshops or training sessions, include case studies and practical examples to illustrate the impact of responsible tracking on user trust and brand reputation.

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Key takeaways

To conclude, here are key considerations to optimize your cross-device tracking practices:

  • Implement transparent cross-device tracking practices to build trust and comply with required laws and regulations.
  • Offer clear opt-in/opt-out options to empower users and respect their privacy preferences.
  • Focus on accurate data matching and secure data handling to prevent user misidentification.
  • Utilize advanced analytics to enhance campaign relevance and effectiveness.

Adopting best practices in cross-device tracking not only enriches your marketing strategies, it also fosters trust and accountability between you and your customers. Prioritizing user privacy will help you navigate the complexities of multi-device consumer behaviour while maintaining customer loyalty.

FAQ on cross-device tracking

What are the key benefits of cross-device tracking?

By tracking user behaviour across devices, you gain a better overview of customer preferences and purchase patterns. This enables you to segment your audience more accurately and ensure all marketing messages are relevant. It also helps reduce your marketing budget by avoiding wasted effort on targeting the wrong people. Additionally, cross-device tracking boosts conversions through consistent messaging and a smoother user experience.

What are the risks of cross-device tracking?

Some users may dislike being targeted with personalized ads, feeling as though “Big Brother” is monitoring them and sharing their information with third parties. It’s important to let customers know how you’re using their data and to obtain consent via opt-in. There are also potential security risks involved in digital data storage, but these can be minimized with protocols such as encryption.

What’s the difference between cross-device tracking and cross-device targeting?

Cross-device tracking involves tracking online behaviour to collect user data and identify when someone is using multiple devices. Cross-device targeting, on the other hand, uses this information to deliver consistent messaging across those devices.

Disclaimer: This article is for general informational purposes only and should not be taken as legal or professional advice. The views and opinions expressed in this article are solely those of the author and do not necessarily reflect the views of our organization. We do not endorse any products or services mentioned in the article.