Replit is a browser-based integrated development environment (IDE) and cloud hosting platform that has evolved into an AI-native app builder, combining code editing, collaborative multiplayer coding, autonomous AI agent development, and one-click deployment. As of mid-2026, its flagship feature is Agent 3 — an autonomous AI coding agent that can plan, write, test, and deploy full applications from natural language prompts within Replit's cloud environment. The platform supports 50+ programming languages, offers built-in databases and hosting, and includes real-time collaborative editing that functions like "Google Docs for code." It is positioned as a zero-setup development environment for learners, prototypers, and small teams who want to build and deploy without managing local tooling. Pricing runs across four tiers: Starter/Free ($0, Agent 3 trial access, unlimited public projects, full IDE capabilities, community support), Core ($20/month billed annually — $240/year total, full Agent 3 access, private workspaces, autonomous app testing, monthly AI credits), Teams ($35/user/month, centralized billing, role-based access control, shared workspaces), and Enterprise (custom pricing, SOC 2 compliance, SSO, advanced privacy controls). The critical billing detail is the credit system: Agent 3 consumes credits per operation, and heavy AI usage can exhaust monthly allocations in as little as 3 weeks of intensive development. One developer reported spending over $5,000 after discovering that annual plan credits are issued monthly rather than as a yearly pool, triggering daily overage charges during front-loaded development sprints. User feedback presents a sharp split. Learners and prototypers praise the zero-setup environment and the speed of going from idea to deployed app — the "Google Docs for code" multiplayer experience is genuinely best-in-class for pair programming and teaching. However, the most common complaint by far is billing unpredictability — "bill shock" from credit overages is the single most cited issue across reviews. Teams note that the $35/user/month pricing escalates quickly (a 5-person team pays $175/month or $2,100/year), approaching enterprise tool costs without matching enterprise depth. The Agent 3 trial on the free tier eventually expires, pushing all serious users toward paid plans. For rapid prototyping, learning, and collaborative MVPs, Replit is excellent; for production workloads with sustained AI usage, the credit model makes costs genuinely unpredictable.