Pocket Lists - World’s Friendliest To-Do List App
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
UpNote - A beautiful and clean cross-platform app for notes organizer
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
Synology Note Station - Without needing to spend money on Evernote, Synology Note Station provides a desktop client to organize all your random notes in one place.
Slack - A messaging app for teams who see through the Earth!