TeXShop is a free LaTeX and TeX editor and previewer. Developed by Richard Koch
License: Open Source
Texmaker is a cross-platform open source LaTeX editor with an integrated PDF viewer. Texmaker is entirely a Qt app. Texmaker is a free, modern and cross-platform LaTeX editor for Linux, macOS and Windows systems that integrates many tools needed to develop documents with LaTeX, in just one application. Developed by Pascal Brachet
License: Open Source
TeXShop is a macOS-exclusive LaTeX editor that offers a simple interface and fast PDF rendering but lacks many advanced features. In contrast, Texmaker is a cross-platform LaTeX editor with a rich feature set, including auto-completion and integrated spell checking, making it suitable for more complex projects.