Protected Audience for Android Interest Group, Bidding, Auction Clarifications/Questions

[thegreatfatzby]

Couple of diffs between Protected Audience for Web (PaW?) and Protected Audience for Android (PaDroid?):

• Not all attributes from PaW seem to be in PaDroid, and while certainly some may not make sense on device rather than in a browser (executionMode in particular) a few others seem relevant from a functionality perspective: priority and priorityVector, adComponents, adSizes and sizeGroups.
• It looks like generateBid is called once per ad rather than once per IG. I definitely see advantages and disadvantages, what is the thinking here?
• Is the IGs userBiddingSignals passed to generateBid in the user_signals parameter? The description here talks about "installed package information" which makes me think about more generic environment info, instead of the IG specific signals...perhaps I'm wrong?
• Similarly on the audience side some of the more operational flags around timeouts and limits aren't there. The timeouts and such are operational but useful and can help with limiting invited IGs (similar to priorityVector).

I guess this leads to two kind of meta questions:

• Is the goal of PaDroid to, within the degree possible given Android and Chrome Browser aren't the same environment, have an implementation and design that aligns with PaW, allowing Ad Techs to implement to the same "idea" even if certain things on the client have to be slightly different? Is this something the "Android Privacy Sandbox" team and leads are coordinating on with the Chrome folks like @michaelkleber @JensenPaul , or should this be seen as a different effort in important ways?
• Related but separate, how should we understand the status of these docs?