Legal
Privacy
DoubleWrite does not directly collect any data on user activity. Other than what is built into iOS, DoubleWrite does not utilize any third party analytics.
Information on iOS data collection (App Store account info, opt-in analytics, etc), and its privacy policy (and full legal compliance information), can be found on Apple's website.
In particular, analytics data collection is opt-in (Settings -> Privacy -> Analytics in iOS) and is aggregated and anonymized using differential privacy techniques to make it difficult or impossible to extract an individual user’s information from the aggregated data. Apple has a document to help illustrate this.
Apple only makes this data available in aggregate and the DoubleWrite developers do not have access to an individual user’s information. For examples of the aggregate data made available, see Apple's page introducing App Analytics in App Store Connect.