Like most, Plex and the *arrs are the main ones, paired with overseerr
Others I use daily or frequently are:
Benotes for bookmarks and quickly saving links for later
Gotify so I have push notifications of anything that happens on the server
Koillection as an inventory of all my knitting and crochet digital patterns
Homepage this one is always a pinned tab on any browser and a shortcut on my phone, quick glance of my services with the widgets and just a click away from them.
Like most, Plex and the *arrs are the main ones, paired with overseerr Others I use daily or frequently are: