What a good iOS app to use a ChatGPT or related LLM thats like the AI equivalent of a VPN

Something that lets you pay but doesn't log the inputs like a blank slate.

I don't mind paying or maybe there's an offline implementation (doesnt have to be cutting edge)

Just looking for text/messaging style app that implements an LLM, preferably not tuned if that limits its inferential abillity

Basically think I'm looking for a talking Wikipedia haha