[ferbivore]

There is some precedent for Apple allowing apps that can be used for ToS or even copyright infringement, as long as they have a plausible legal purpose and all the infringement happens through third-party plugins that are not advertised in the app. The example I'm most familiar with is Paperback. There's also precedent for Apple not caring about Google's terms in particular, e.g. with Musi, though I guess that did get taken down in the end.

Grayjay also uses a plugin model, possibly for this exact reason. On the other hand, the infringing plugins are first-party and advertised via their website, so I somewhat doubt that either Google or Apple would allow it on their stores.