Unfortunately, I'm trying to learn Greek and every aspect of it is sub-par compared to other languages. It doesn't even read you questions correctly. (It uses flat intonation as if it's saying a statement.) There are no vignettes like in Spanish and French where you watch a conversation and then summarize what was said. They just throw in new concepts with no instruction whatsoever. So you see a word that you know is a verb, but the ending is one you've never seen before. There's no chart or examples, or even explanation that "now we're going to teach you past tense," or whatever. Just suddenly there's a bunch of new stuff you don't understand and you have to go to the Internet to look up what the hell is happening. God forbid you ask a question on the forum. The Greek mods are stereotypically rude and controlling. Nothing is ever the fault of the app, it's always the user's fault, even when native English speakers are telling them, "The English translation of this sentence doesn't make sense and is not valid English."
So yeah, I'm definitely not going to pay for an AI that is likely giving wrong advice anyway.