Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.
Endpoints - View and respond to requests on an HTTP endpoint
Relicx - Relicx enables developers to debug front-end issues fast with session replay, auto-generate end-to-end tests based on real user flows, and release faster by measuring CX risk in your CI/CD pipeline.
httpbin(1) - HTTP request and response service
code-ray - Live debugging tool for software developers