I've never put too much thought into the tools I use online. Now that I do, here's a list of the tools that I find useful for:

Knowledge management

Frankly the best digital tool I ever found. Continues and continues to grow, and I keep coming back to it even after five years and it keeps getting better: TiddlyWiki

Project management

Free forever, easy to use, great functionality Clickup

Open Source, Free to use, point scores! Taiga

Video conferences

Disroot calls powered by Jitsi

Collaborative writing

Disroot pads powered by Etherpad Lite

As you can guess, I'm already a fan of But the site that led me to all these tools is PrivacyTools

Route planning

For bike and walking routes Komoot