Replit Agent 4 Is UNBELIEVABLE - I Can't Believe It Can Do This

Replit Agent 4 introduces several new features for building SaaS products: an infinite canvas for visual design iteration, parallel task execution, multi-artifact projects (web app, mobile app, pitch deck, promo video all in one project), and collaborative task management. The canvas allows sketching, comparing design variations, and switching between interactive and design modes. Parallel tasks let multiple changes run simultaneously without waiting, with a review step before applying to the main version.