Asklemmy

Apples Notes because nothing else has the perfect amount of formatting, alongside exceptional sync.

Also Apple Mail for the same simplicity reason - Geary on Gnome is close-ish, but goes too far down the simple route. How does it not have a refresh button??

Also Logic Pro, mainly because there aren't any fully FOSS alternatives that even attempt a full-featured DAW, let alone with Drummer etc.

I also 'prefer' Apple's productivity suite over everything else, because it has by far the best UX, but I'm totally fine with LibreOffice too.

There's a few open source front ends for Twitch that I've tried but I've had the occasional issue with video playback either stopping and being unable to reload or if I'm watching a VOD it won't consistently remember my position so I'd say I prefer the official app.

Normally I use open source ones when possible such as NewPipe or Invidious for YouTube for example.

Termius saves me so much time as an engineer connecting to the dozens of servers in our infrastructure

MacOSf or the trackpad gesture support.