AI-powered English conversation practice
Project Overview
What We Worked On
- Voice-to-Voice AI Integration
- GPT Realtime API Implementation
- Conversation Practice Interface
- Progress Tracking System
- Mobile-Responsive Design
- User Authentication
Background
VocalEnglish targets French speakers who want to practice conversational English but lack native speaker access. The platform uses cutting-edge voice AI to provide realistic conversation practice available 24/7, adapting to each user's level and interests.
The Challenge
- Language barrier — Traditional apps focus on reading/writing, not speaking.
- No conversation partner — Most learners don't have access to native English speakers.
- Intimidation factor — Many learners are too shy to practice with real people.
- Limited practice time — Tutors are expensive and scheduling is difficult.
- Generic content — Most learning content doesn't adapt to individual interests.
The Solution
Phase 1: Voice AI Foundation
Integrated OpenAI's GPT Realtime Voice API to enable natural voice-to-voice conversations with sub-second latency.
Phase 2: Conversation Experience
Designed an intuitive interface for voice conversations with visual feedback, topic selection, and difficulty adjustment.
Phase 3: Learning Features
Added progress tracking, vocabulary building, pronunciation feedback, and session history.
Results
Response latency
Real-time
N/A<500ms
Practice availability
Always on
Limited24/7
Cost vs tutor
-80% cost
CHF 50+/hourCHF 10/month
Session length
High engagement
N/A15 min avg
- Accessibility: Practice English anytime without scheduling
- Confidence building: Low-pressure environment encourages speaking
- Personalization: AI adapts to topics the user cares about
Technology Stack
What's Next
- Pronunciation scoring — Detailed feedback on accent and clarity
- Lesson modes — Structured learning paths for beginners
- Group conversations — Practice with AI + other learners
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