Netlify has made significant product improvements in April 2021, including On-Demand Builders for faster build times on large sites, Netlify Labs for in-app beta testing, and auto-detection of Next.js for improved development cycles. Other updates include native TypeScript support for serverless functions, dark mode, modern and faster Netlify Functions, zero-config deploys, a Netlify Functions playground and examples site, linkable log lines, function logs color coding, and auto-scroll pause. These changes aim to improve the overall experience of users, enhance productivity, and provide better tools for developers.