When comparing Dia vs Coggle, the Slant community recommends Dia for most people. In the question“What are the best flowchart / diagram softwares?” Dia is ranked 8th while Coggle is ranked 13th.
Ranked in these QuestionsQuestion Ranking
Pro Free and open source
Pro Tons of icon sets
Has flowcharts, uml, chemical engineering, electronics, and dozens of other complete sets, built in.
Pro Custom gzipped XML format
Pro Supports Markdown (their own variant)
Markdown is a plain text formatting syntax designed so that it can optionally be converted to HTML using a tool by the same name.
Coggle allows inviting friends and colleagues to work collaboratively on notes and diagrams in real-time.
Pro Pretty diagrams
No effort to create beautiful diagrams.
Pro Supports LaTeX
LaTeX is a document preparation system and document markup language. It is the de facto standard for the communication and publication of scientific documents.
Pro Allows easy color-coding of paths
Pro Versioning support
Enter history mode to view all changes to a diagram over time, and make a copy from that point.
Pro Optional Chrome store App
Pro Lots of export options
Exports to PDF, image, plaintext and .mm files.
Dia has not been updated since 2009. It's already a very complete piece of software, but still sad.
Con UX is a joke
UX is not good enough. For example, to edit element text you must double-click it, then click text box, and then you can start typing text.
Con Tree relations only; no non-parent links
Coggle's model allows a node to have multiple children, but only one parent, and no other connections of any sort.
Con Unconventional note taking style
Coggle is a mind mapping application, not a traditional text based note storage platform.