I myself have no iPhone. And I dolnot yet know about a similar app for android. Would be great to know, what data every app can get. To me there is a clear winner, when it comes to craziest tracking: Meta and Yandex breaking Androids Sandbox in order to connect browser activity to a specific user.

gHacks

Meta caught breaking Android's sandbox by monitoring web browsing through its apps - gHacks Tech News

Meta and Yandex have implemented tracking methods on Android that de-anonymized a user's web browsing.

They broke the sandbox. So lets say you are logged in to Facebook, but in the browser you are not logged in. In whatever Event, when a website got a Facebook tracking pixel, they would be able to link this to your Facebook account through an Android sandbox exploit. Means they could track millions of internet users persistently through the internet.