Fiddler - Fiddler is a debugging program for websites.
ngrok - ngrok enables secure introspectable tunnels to localhost webhook development tool and debugging tool.
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
GlassWire - Visualize network activity in detail, get notified when new apps access the network, look out for...
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.
TrafficMonitor - TrafficMonitor is a network monitoring suspension window software in Windows.