Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
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.
TeXworks - The TeXworks project is an effort to build a simple TeX front-end program (working environment)...
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
Texmaker - Texmaker, free cross-platform latex editor
Slack - A messaging app for teams who see through the Earth!