Recently doing some debugging on my home network and found this app to be quite helpful. I'm quite comfortable with the shell, and did some debugging on my Mac, but only the phone (and iPad, but see below) had the problem I was troubleshooting so I needed to work there. The app does exactly what it says. It works well. It's got a minimal UI that uses default iOS controls but that's all it needs--anything else would be overwrought.
The only thing that's missing is I'd love to have a proper iPad version. It doesn't need to be anything special, all it needs is an iPad-size UI. The stock iPhone app scaling is pretty unpleasant to use, especially in landscape--I've got an iPad Pro with a keyboard attached all the time, so I never use it in portrait.
All that said, though, to reiterate, this is a great app on the iPhone which makes troubleshooting Bonjour stuff a lot easier than it would be otherwise!
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