Suggest improvements to UI / UX of language learning mobile app

I built and run my own app to learn the Italian language. I often hear from users the typical UX complains: hard to navigate, can t find things, dont know what to do, etc. But when asked what exactly is wrong users can't or won't say. As the author myself, I take things for granted and thus can't assess objectively. I need expert advice to improve the UX on my app. Anything from look and feel to information architecture to I don't know what... Focus on the mobile app (not the web app). Start from onboarding, through the main learning screens, to the settings sheets etc. You dont need to rebuilt the whole app UI. Only give advice, general or specific to screens. If one piece of advice applies to multiple screens, only show me the suggested version of one screen. Deliverables can be screencasts, hand drawings, figma, etc. Whatever is faster for you. I will forward your advice to Claude Code together with image, videos or figma assets to replicate. You're free to use AI to illustrate your suggestions, but I expect human expertise (I can show my screenshots to Claude Code by myself). You're welcome to see for yourself. The app can be installed for free on the App Store and Play Store. No in-app purchases needed. All features are available to guests (you will hit usage limits) . Free signup is optional. https://speaktwice.app I can give you full access later so that you don't hit usage limits (it's freemium). I won't show you around because I don't want to influence your first impressions. Start your application with my name (Stefano).