Qustodio - Free parental control software. Monitor and track your child's online activity. Block dangerous sites and protect kids from online bullying.
Surge for Mac - Advanced Web Debugging Proxy for Mac & iOS
HomeGuard Activity Monitor - Monitor and block Web activity, keystrokes, limit gaming time and record screenshots.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy
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.
HTTP Headers - HTTP Headers allows you to quickly see the HTTP header information for the current URL.