HeySpace - HeySpace is the only free task and simple project management software with communication and collaboration feature.
Better Notes - Simple notes app that ties notes together with #hashtags
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.
Collected Notes - Simple and powerful note-taking & blogging platform.
Taskade - Make lists, organize your thoughts, and be inspired to get things done. Taskade is a collaborative space for your tasks.
Startup Notes - Most actionable advice from each Startup School speaker