ZenHub - ZenHub is how the world's best software teams work together. Trusted by NASA, Docker, and Rackspace. Start free today!
Notebook.ai - A smart notebook that grows and collaborates with you
Nifty - Manage projects, work, and communications in one place.
Beastnotes - A notebook for online courses
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.
Stickies Capture by Miro - Digitize and edit handwritten sticky notes