I really enjoyed this demo and I can't wait to see more of the game! I'm a language lover and, just like you, I can't really retain things from just studying with apps. The real-time, real-conversation aspect of this is so cool!
If it's possible, I think an on-screen keyboard for the target language would be really helpful. I have a physical one that has both English and my target language's layout, but I'm sure not everyone does. So, that would be really cool to possibly see in the future :)
Thank you for making this; keep up the amazing work!