Vowelly

Vowelly is a real-time speaking practice web app for English, Mandarin, and Cantonesethat lets learners talk naturally with an AI conversation coach. It combines live voice interaction, transcription, and accent-aware guidance to make short, focused practice sessions feel practical and low-friction. The app currently includes trial-limited access and is evolving toward full account-based usage.

Design

  • Clean, single-page-first interface with a strong focus on voice interaction and minimal setup
  • Responsive layout for desktop and mobile with lightweight navigation across key pages
  • Real-time visual feedback through waveform/equalizer and status chips for connection and listening state
  • Clear trial and lifecycle messaging (session state, limits, and post-trial next steps)

Key Capabilities

  • Live voice conversation with AI coaching in multiple language tracks
  • Real-time transcript rendering for both user and assistant turns
  • Language/accent-aware prompting and warmup flows to guide pronunciation practice
  • Server-side session token generation with secure API key handling and controlled trial access

Key Behaviors

  • Establishes mic + realtime session, updates UI states as users speak and AI responds
  • Enforces usage limits (home preview cap and aggregated network-based Speak trial cap)
  • Logs and finalizes session usage to support trial governance and reconnect handling
  • Shows post-limit guidance banner encouraging waitlist interest and communicating upcoming account features

Tech Stack

  • Frontend: vanilla HTML/CSS/JavaScript (ES modules), no heavy framework dependency
  • Realtime: WebRTC + OpenAI Realtime API for low-latency voice interaction
  • Backend runtime: Cloudflare Pages Functions (Workers runtime) for API endpoints
  • Storage/security: Cloudflare KV for trial ledger persistence + secret-managed API key

Screenshots

Placeholder: Voice Flow Screenshot
Placeholder: Prompt Screen Screenshot
Placeholder: Recovery Path Screenshot