Anytime you download an app, by default ir has permission to use your Cellular Data and WiFi and indexed by Siri. Best you can do is void all those and not give it any unnecessary permissions

If you have enough data (like 50+GB), try to keep WiFi off and use only cellular and disable the apps celllular oermission in the Cellular section in Settings

Its beyond irresponsible it wasn’t pulled the moment the most recent revelations came about. It also made me wonder if Apple “sees” certain fields of your keychain items, in-line with their conflation of convergent encryption as e2ee and other assorted privacy antics