ModSecurity - ModSecurity is an Open Source web application firewall developed by Trustwave's SpiderLabs.
Surge for Mac - Advanced Web Debugging Proxy for Mac & iOS
AWS WAF - AWS WAF is a web application firewall that helps protect your web applications from common web exploits.
Weer - A HTTP protocol debugger with Chrome DevTools frontend interface
Barracuda Web Application Firewall - Barracuda Web Application Firewall offers security and DDoS protection against automated & targeted attacks.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy