Based on our record, GitBook seems to be more popular. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
You can have both a landing page (e.g.: www.your-project.dev) and a documentation website (e.g.: docs.your-project.dev). For creating documentation website GitBook is better fit than Gitlanding. GitBook is free for open source Projects (you just need to issue a request). - Source: dev.to / about 2 years ago
GitBook is a collaborative documentation tool that allows anyone to document anything—such as products and APIs—and share knowledge through a user-friendly online platform. According to GitBook, “GitBook is a flexible platform for all kinds of content and collaboration.” It provides a single unified workspace for different users to create, manage and share content without using multiple tools. For example:. - Source: dev.to / about 3 years ago
draw.io - Online diagramming application
Docusaurus - Easy to maintain open source documentation websites
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
MkDocs - Project documentation with Markdown.
yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.
Doxygen - Generate documentation from source code