Lovable (formerly GPT Engineer) is an AI app builder that generates complete full-stack web applications — Next.js frontend, Tailwind CSS styling, Supabase backend, and authentication — from natural language prompts in a browser-based chat interface. As of mid-2026, the platform has become one of the fastest-growing AI products, reportedly hitting $50M ARR in under 12 months since its 2024 founding. Users describe a prompt-to-deploy workflow: describe the app, watch it generate code, preview changes live in seconds, and deploy with one click. A critical differentiator is the export-to-GitHub flow, allowing users to push the entire codebase to their own repository and continue development in Cursor, VS Code, or any standard IDE. Pricing is message-based: Free ($0, 5 messages/day — enough for a basic landing page demo), Starter ($20/month, 100 messages/day), Launch ($50/month, 250 messages/day), and Scale ($100/month, 500 messages/day). A "message" equals one prompt-response cycle, which may edit multiple files. Annual billing is not prominently advertised; monthly is the standard. The platform is entirely browser-based with zero installation, making it accessible to non-technical founders who have never opened a terminal. User feedback is enthusiastic for the first 80% of any project. Reviewers consistently praise the UI quality as the best among AI app builders — sensible component patterns, decent typography, and mobile-responsive layouts by default. However, the consensus verdict is clear: Lovable excels at prototyping and MVPs but hits a wall on the "last 20%" of production work — custom business logic, complex authentication flows, third-party integrations beyond the default Supabase/Stripe path, and edge-case handling all require manual intervention. The message-based pricing also burns quickly; reviewers report the Starter plan's 100 messages lasting roughly 3 hours of serious development, making Launch or Scale necessary for anything beyond hobby projects. The winning workflow appears to be: prototype in Lovable, export to GitHub, finish in Cursor.