Two AI app builders, side by side. Facts below link to their sources; last checked 2026-10-17.

Chat-based builder for real websites and web apps, evolved from the open-source gpt-engineer project and the gptengineer.app platform. source

Online development platform with Replit Agent, which builds apps from natural-language descriptions; Agent 4 adds Design Canvas, shared collaboration and parallel tasks. source
Lovable: Build and publish full-stack web apps by chatting with AI. Replit: Browser IDE whose Replit Agent builds and deploys apps from a description.
Lovable: From $25/month (free tier available). Replit: From $20/month (free tier available). Prices change often; confirm on the official pricing pages.