BlankPage - Stay motivated to write, and finish your story
Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
Novelize - Novelize is an online novel writing app designed to keep authors on track.
TeXworks - The TeXworks project is an effort to build a simple TeX front-end program (working environment)...
Manuskript - Open-source tool for writers.
Archimedes - Archimedes is a LaTeX and Markdown editor designed to make mathematical writing easy.