What are best practices for attributing app opens to Facebook remarketing campaigns?

Localytics has a native integration with Facebook that allows us to automatically detect when a user launches your app after clicking on a Facebook App Engagement ad (e.g. when a user clicks ‘Learn More' or ‘Open in App' from a Facebook ad). This will be reported in the Remarketing module within the Localytics dashboard. 

However, you might additionally want to identify users who came from Remarketing campaigns to measure the downstream impact. You can achieve this by: Setting the goal URL for your Facebook re-engagement campaign as a deep link with UTM parameters; configuring your app to collect that referrer information;and handing off that referral information to Localytics as either a Custom Dimension or an Attribute on an Event. 

Here's an example workflow: 

A user clicks on a Facebook re-engagement advertisement. That advertisement includes a goal URL such as: 

exampleAndroidApp://launch?location=123456&utm_source=facebook&utm_campaign=ExampleCampaign 

        </li>
        <li>
          The app is configured to grab the utm_source and utm_campaign parameters at the end of the link and store those temporarily.
        </li>
        <li>
          When the app opens, the app is configured to either write a Custom Dimension using the temporarily-stored information or write an Attribute on an Event that is tagged within Localytics.
        </li>
    </ol>