I installed the Fixd app (iOS) to use the OBD2 reader I'd just purchased for $50. The app immediately contacted amazon, google, criteo, apple, and a handful of others. How do I prevent that from happening?

I thought something like NEXTdns would allow me to set a rule to block apps from phoning home, but apparently not. Are there any applications that will allow me to set up rules that will prevent apps from sending usage data to... well, anyone?

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