Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.

MacDown - MacDown is an open source Markdown editor for OS X, released under the MIT License.

Fidus Writer - Fidus Writer is an online collaborative LaTeX editor especially made for academics who need to use...

Frost - An open API for Blockchain timestamping

TeXworks - The TeXworks project is an effort to build a simple TeX front-end program (working environment)...

Typora - A minimal Markdown reading & writing app.