Track traffic movement across platforms (Website and Mobile APP)

@rahul_2 the ECID is a random value that gets generated and persisted on your device as a cookie.
So, this won't be usable across devices. The internal campaign information is attached to this ECID on Adobe's servers

There is a cross-device tracking feature in AA called Cross-Device-Analytics (or CDA), that requires

• a specific license and AA Ultimate
• a user id that is available on both devices, like a login or CRM ID. This is can then be set up to be used as stitching identifier

https://experienceleague.adobe.com/en/docs/analytics/components/cda/overview

There is an App to Web solution, that allows you to pass the ECID from your mobile app to your website (when people click on links inside your app to your website).

Unfortunately, this does not work in reverse (web to app), and since I don't know if the user had a previous ECID on web, if that would get stitched to being the same user, or basically you overwrite the user identification for web. It's also possible that if the website opens in a webview that the cookies are kept unique and separate from using the website normally in your browser.

Because of the limitations of this solution, and the fact that we have minimal webviews in our apps, it's not a solution I have investigated much.

Here is the documentation if you choose to pursue this investigation:

https://experienceleague.adobe.com/en/docs/experience-platform/web-sdk/identity/id-sharing

As @bjoern__koth mentioned, there is also the Cross-Device-Analytics, however, this is no longer sold to Adobe Analytics clients... if you already have it, great... if not, the only way to not get access to it is by getting CJA....