I really love PowerPoint. I feel like the automatic snapping features and general polish allow me to make very pretty slides 
with a high level of control, and it feels way better to use than e.g. web-based alternatives. Admittedly, I haven't tried a foss alternative in years.
Topaz photo software and Mendeley Desktop
At least topaz fulfills one of the aspects of foss by being very easy to pirate /s
I have an iPhone. While VLC is good, foobar2000 Mobile is really the only free music player that works the way I want.
iTunes no-longer runs under Wine, so the official Music app is not an option.
EDIT: Clarified that I meant the Apple Music app, not the streaming service.
If you can get past how questionable the developers are, Cider is an option for using Apple Music on Linux.
Affinity Designer 2 and maybe DAZ Studio. I would pay got money if those could get ported to Linux. A Man can dream 🤷♂️
@AHYN018 Letterboxd and TheStoryGraph that I maintain as diaries of what i am watching and reading.
Are they ethical though? (Serious question as I'm uninformed)
Both are directly tracking what you watch/read so I would worry that they might sell this data to others.
Lightroom
Listonic for shopping lists etc. KDE Connect Proton - Mail, Calendar, VPN, Pass, Drive AdGuard Songs Wavelet Pulsar+ NHS app Radio Paradise
elsa speak.
Czech maps from Seznam, I talked with marketing boss (don't know his exact position but it is high) and he told me that they don't make money from it.
If any one is interested mapy.cz it is must have app for travel in Czech.
If it's free and open source and it's also software, it can be discussed here. Subcommunity of Technology.
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