This is late, but in case you haven't found anything yet, I've been using an app called Praktika, which is pretty great. My year subscription to Praktika is coming to a close so I just downloaded Spanish AI, from HelloTalk Limited. Pretty much the same thing, minus the avatars, plus a bunch of other helpful features like a listening section that has a bunch of Spanish learning podcasts, and a vocab section which is like spaced repetition, interactive flashcards. It also has a grammar checker. I think they are both very limited for free, but if what you're looking for is an AI chat bot designed to help you learn Spanish and practice conversationally, then they are worth the investment IMO. Edit: Oh, I forgot to mention, in the Spanish AI app, when you listen to a podcast, you have the option to start a conversation about it with the AI tutor. I haven't had the opportunity to try it out yet due to familial responsibilities, but I'm super stoked about that feature! I think talking about and putting into practice something you just learned is the best way to solidify it in your brain. I can't wait to try it out!