Repetition, is the path to mastery. What is this application about? Simply having lessons of the language you need to learn, with an AI teacher. You can write or talk , writing is kind of easy, and talking is a bit more challenging.. you can learn from different level of mastery. in my case , I can learn more vocabulary in English where I have a great experience practicing, it can adapt to my schoolish spanish or my absence of knowledge in German. It have a paywall. But it's worth it.