Overleaf is a collection of real-time collaborative writing and publishing tools.
License: Freemium
Apps available for Online
GNU TeXmacs is a free scientific word processor and typesetting component of the GNU Project.
License: Open Source
Apps available for Mac OS X Windows Linux Xfce
TeXmacs is best suited for users who prefer offline work and customization, while Overleaf shines in collaborative environments and accessibility. Overleaf's cloud functionality contrasts with TeXmacs's desktop-centric approach.