I'm giving up on SF support, so figured I'd try here instead. I am exploring mobile push and need to understand what's happening on a data side. I see this image from contact builder:

This table - mobile push demographics - how does this become populated?

I'm struggling giving that the SDK Documentation states that we should use ContactKey / SubscriberKey, however I don't see this attribute anywhere - and it isn't used to link to all subscribers.

So if i have an externally managed subscriber key - meaning that new subscribers can come into my platform by downloading the app first, and i generate the subscriber key and then push that into the marketing cloud - then this is before they actually have a contact id.

Can someone explain how this process works / should work ?

I am exploring mobile push and need to understand what's happening on a data side. I see this image from contact builder:

This table - mobile push demographics - how does this become populated?

I'm struggling giving that the SDK Documentation states that we should use ContactKey / SubscriberKey, however I don't see this attribute anywhere - and it isn't used to link to all subscribers.

So if i have an externally managed subscriber key - meaning that new subscribers can come into my platform by downloading the app first, and i generate the subscriber key and then push that into the marketing cloud - then this is before they actually have a contact id.

Can someone explain how this process works / should work ?