Last I checked all browsers on IOS are required by Apple to be basically a reskinned Safari.

What do you mean by “stay alive”? LLMs are statistical models that require a lot of number crunching in order to output a response. That’s not something you can just host without some major costs associated (Far more than any single Fediverse instance for sure, GPUs are not cheap to rent).

Probably referring to free open-source software and not just free to download.

There is a one time purchase option. The subscription is for features that need additional cloud services.