I’m playing around with some things that require me to prevent an app from being able to connect to the Internet. I know I can just shut off the Internet en toto, but I’m wondering if it’s possible to just shut off access for a specific app.
I’m assuming this would require an app of some sort to play “man in the middle”?
Any thoughts about how I might achieve this?
Not sure if the MacOS native firewall can do it but something like LittleSnitch can block outbound traffic for all or part of an app’s traffic.
Alternatives that I found but have no experience with are TripMode, LuLu, and Radio Silence. TripMode being the only one of the three I had heard of previously.
I do this with an app called Freedom
That looks interesting. I know it has a trial that I can check out, but do you know if I can say that I want to be able to run the app, but not have it go online?
I don’t see how to block anything other than incoming traffic in the firewall. Which isn’t what I’m hoping for.
I’d completely forgotten about LittleSnitch. I’ll check out their demo. 
+1 for Little Snitch, it allows for fine grained control of an app’s outgoing connections.
I also use Little Snitch for this exact purpose.
You can also use TripMode to block access to specific app(s). It’s available on Setapp and on the Mac App Store.
Totally recommend both LittleSnitch and TripMode. I use the latter whenever I’m tethering on the train or at remote offices - really trims the data usage down. Very easy to use too and with it being on Setapp, another good use of that subscription.
I think TinyShield from the Proxyman developer can do exactly that:
It’s currently on sale (Black Friday, 60% off) and uses the “Agenda licensing model”.
Disclaimer: have not tried it myself. I use Little Snitch for this - and Proxyman for capturing/mocking HTTP(s).
PS: Also included in Setapp
Huh, is the Setapp preview above in German for everyone?
That’s not my native language and I’m not in that country…
I can confirm that Tiny Shield is also available in English on Setapp. I’ve never used Tiny Shield. Looks like an interesting app.
It shows as German for me. I think it may be the country that SetApp is run from. In another forum I post links to a French company’s site and the previews (in the same forum software) appear in French, even though the page I was on was in English.