Surge for Mac - Advanced Web Debugging Proxy for Mac & iOS
Qustodio - Free parental control software. Monitor and track your child's online activity. Block dangerous sites and protect kids from online bullying.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy
CurrentWare BrowseControl - BrowseControl web filtering software blocks websites based on URLs and categories. Policies can be customized for each user, department, or OU. Includes other features such as an app blocker, port filter, and download/upload blocker.
HTTP Headers - HTTP Headers allows you to quickly see the HTTP header information for the current URL.
K9 Web Protection - This also contains the feature “Blacklist Without Password” which allows non-admin users to add sites to the “Always Block” list without requiring the K9 admin password.