Fiddler - Fiddler is a debugging program for websites.
Next-Generation Intrusion Prevention System (NGIPS) - Cisco Firepower NGIPS (Next-Generation IPS) provides contextual awareness, security intelligence, and advanced threat protection against attacks and malware.
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
snort - Snort is a free and open source network intrusion prevention system.
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.
Suricata - Suricata is a high performance Network IDS, IPS and Network Security Monitoring engine.