I’m looking for a spaced repetition alternative to Anki, ideally something that I can self host and expose like any other webapp, and that is compatible with .apkg Anki decks (or at least that is compatible with something I can convert .apkg decks into). I’d like to not have to create an account with Anki or some other third party, and wasn’t super happy with anki-web and the anki-sync-server container – but maybe I was just using that wrong…
I haven’t personally set it up yet but you can enter a custom self-hosted sync server in the desktop app’s settings. No need for an ankiweb.net account.
As for iOS, choosing a mostly unfree platform means you get the unfree experience and its consequences. Anki couldn’t even publish a copyleft app on the app store if they wanted to. See the $25 as the Apple tax ;)
For the free-ish mobile platform, there’s https://github.com/ankidroid/Anki-Android.