1) Nuclear - Desktop music player focused on streaming from free sources (in beta phase):
Nuclear Mastodon account: @nuclear
2) Pidgin - IM with options to add various third party plugins which enables you to use facebook chat, steam chat, etc, XMPP included.
3) Synchting - cross platform peer to peer file synchronization, also available on f-droid:
I forgot about one, I use it everyday.
Freetube - Open source YouTube player which uses youtube-dl for playing videos, also capable of subscriptions with no google account needed and with routing over tor network. It even uses invidio.us API, which is privacy oriented YouTube frontend.
And I forgot another one! 😀
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