Who buys this
Intermediate language learners who can read a textbook fine but freeze up the moment they have to speak in a real conversation.
Where to start in Lovable
Paste this into Lovable as the opening prompt. It sets up one screen and one job, which is easier to grow from.
Build a conversational practice chatbot where the user picks a target language and a scenario like ordering food or a job interview, then has a spoken or typed back-and-forth conversation with the AI staying in character for that scenario. After each exchange the AI gently corrects grammar mistakes in a side panel without breaking the conversation flow, and at the end shows a summary of recurring mistakes across the session.
What you will need to wire up
- Lovable AI Gateway
- Lovable Cloud (Postgres)
- API de fala para texto e texto para fala
- Autenticação de usuário
Build order
- Lock the scenario persona in the system prompt. Write a strict system prompt per scenario that keeps the AI in character, refuses to break into teacher mode mid-conversation, and only surfaces corrections in the separate panel. Mixing roles in one reply confuses learners about what is real dialogue and what is feedback.
- Get typed conversation solid before adding voice. Voice adds latency, transcription errors and a whole new failure surface. Ship a working typed chat with the persona and correction panel first, then layer speech-to-text and text-to-speech on top.
- Track mistakes across turns, not just per message. Store each correction with its grammar category in the database as the session runs so the end-of-session summary can group recurring patterns like verb conjugation or gender agreement, which is the part learners actually act on.
- Add a difficulty dial the learner controls. A slider for vocabulary complexity and speaking speed keeps intermediate learners from bouncing off a chatbot that talks like a native speaker on day one, and keeps advanced learners from getting bored.
Where this usually breaks
- Speech-to-text accuracy drops hard for accented speech and background noise, so the bot corrects things the user never actually said. Show the transcribed text before responding so the user can fix it, rather than reacting silently to a wrong transcript.
- The model breaks character and starts explaining grammar rules mid-roleplay when asked a tricky question, which kills immersion. Add a hard instruction to redirect grammar questions to the correction panel and keep the roleplay reply short and in-scenario.
How it makes money
- Monthly subscription with a minutes-per-month cap. Speech APIs are billed by usage so a cap protects your margin while still feeling generous for daily practice.
- One-time scenario packs sold as add-ons. Learners who finish the free scenarios will pay once for a themed pack, like travel or business, without committing to a bigger subscription.
Build this on Lovable
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