I spend a lot of my professional working life using a serial terminal to configure routers, switches, and servers. Serial terminal applications on OS X were always a mixed bag. Most of the ones that came up a lot in searches haven’t been updated in ages. Add to that the fact that OS X has a mixed history with driver1 support for USB to serial devices and you have a perfect storm of frustration and the one area where Windows was actually a better OS choice2
Serial is an overwhelmingly great serial terminal. It includes drivers! It’s just a serial terminal, not a kitchen sink app. It does one thing well. And I love it. If you spend any amount of time in a serial terminal, Serial is the app you’ve been waiting for.