Frankly, I don't think Little Snitch is usable because of this. And no, a lookup tool is not good enough. For a paid program, I would expect them to maintain a list of the "required/acceptable" connections and "unnecessary" connections for popular programs, and automate the process of approval for each app.

Perfect example: Spotify is impossible to manually whitelist without spending well over an hour accepting or denying each of the exhaustingly large number of domains it touches. I bet that nearly every user simply gives up and whitelists the entire application, which defeats the purpose of paying for and installing an app like Little Snitch in the first place.

Little Snitch should be doing that work up front for its users. One person on their end spends a day or two figuring it out for an app, and saves tens of thousands of user hours having to individually perform that task. No anti-virus out there alerts a user to every filesystem read and write - they maintain databases of known threats. The same should be true for this kind of software.

Yes, it would require constant maintenance on their part. If they needed to up the price to make such a strategy viable, so be it. As it stands, I uninstalled out of frustration after using the demo for 6 hours. The alerts and interruptions never stop.