Surge for Mac - Advanced Web Debugging Proxy for Mac & iOS
Squid Proxy - Website Content Acceleration and Distribution. Thousands of web-sites around the Internet use Squid to drastically increase their content delivery. Squid can reduce your server load and improve delivery speeds to clients.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy
Polipo - A small and fast caching web proxy (a web cache, an HTTP proxy, a proxy server).
HTTP Headers - HTTP Headers allows you to quickly see the HTTP header information for the current URL.
AdGuard - Surf the Web Ad-Free and Safely. Shield up!