MacGDBp

Overall, a pretty good and solid debugger for my needs. The configuration on the web server is what may turn many off to using a debugger with PHP, but the results can be well worth it.

MacGDBp isn't very useful for Xdebug 2 that defaults to the DBG protocol — Xdebug 2 being what you really need to use with PHP 7.x — so this app is now obsolete unless you run Xdebug with the GDB protocol. See this answer https://stackoverflow.com/a/4849558/427009 for using GDP.

I set up debugging in Eclipse with PDT (PHP Developer Tools) instead and use Apache in Mamp together with a browser plug-in. See https://www.jetbrains.com/help/phpstorm/browser-debugging-extensions.html

It was good, but unfortunately is not updated since years and crashes continuously. Codebug was a good alternative, but that one also got discontinued.

really good product :)

Developer's web site up but the download link is dead...

Note to site admins: version 1.5.0 is now out.

Overall, a pretty good and solid debugger for my needs. The configuration on the web server is what may turn many off to using a debugger with PHP, but the results can be well worth it.