Gufw - Gufw is an easy, intuitive way to manage your Linux firewall.
NetLimiter - NetLimiter is an ultimate Internet traffic control and monitoring tool designed for Windows.
NetBalancer - NetBalancer is a Windows application for local network traffic control and monitoring.
Little Snitch - Little Snitch is a firewall application that monitors and controls outbound internet traffic.
Portmaster - Is a Privacy Modular Privacy App which includes a "DNS over TLS" feature as well as an "Application Firewall".
TinyWall - Lightweight and non-intrusive firewall