OpenSnitch is modeled after LittleSnitch: It intercepts connections and if there is no rule that matches, it asks you what to do. This is a very simple and effective tool, IF you know your way around all the technical stuff and understand what these prompts tell you.

The Portmaster is aimed to bring privacy to everyone, even and especially to non-technical people. No worries, there will loads of stuff for all the hardcode people! While there is a similar “ask” mode to Open/LittleSnitch (currently still broken and classed as an experimental feature, sorry), the focus is on more intelligent functionality:

• Restriction via network scope: Localhost, LAN, Internet
• Ability to deny any peer to peer communication (connections without associated DNS query)
• Integrated DNS-over-TLS resolver
• Ad/Tracker/Malware domain based filter lists with hourly incremental updates
• Security Levels to quickly switch between settings to adapt to threats
• … and so forth
• In addition to all this, we will launch the biggest feature of all soon, the SPN, a brand new privacy network that somewhat compares to Tor and VPNs, but still is different: https://safing.io/spn/

Important note: The Portmaster is still in alpha, but it works quite well!