Some ads are designed to allow users to install or install a deep link to installed applications. These flags indicate whether the advertising identifier is used to track these types of behavior.
So these two questions ask:
1. Are you going to use IDFA to track users who install your application from ads?
2. Are you going to use IDFA to track users who follow deep links to your app from ads?
The IDFA is used so that marketers can measure advertising performance. Here's an article that talks about this in relation to a particular vendor SDK.
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