When comparing Creately vs PlantUml, the Slant community recommends PlantUml for most people. In the question“What are the best flowchart / diagram softwares?” PlantUml is ranked 16th while Creately is ranked 20th. The most important reason people chose PlantUml is:
For example from Emacs, Sublime Text and so on. You can learn about integrations [here](http://plantuml.com/running).
Ranked in these QuestionsQuestion Ranking
Pro Professionally designed templates
The templates are well thought-out and actually helps you get started. Not like many other sites where the details are already filled in.
Pro Intuitive UI
Easy to use drag and drop interface and a contextual toolbar that shows you all the important actions when you select an object. The automatic creation and connecting of next object alone saves tons of time.
Pro Real time collaboration
You can invite anyone by their email addresses to collaborate with your diagram. You can see others' changes to the diagram real time with the Creately Online and Desktop app.
Pro Visio Import
Pro iSO and Android apps to view diagrams
You can't edit diagram using the apps but provides a nice clean interface to view, share and comment on them.
Pro SVG import and export
Creately supports SVG (Scalar Vector Graphics) import and export to make your diagrams more attractive. It allows you to re-size your diagram as much as you want without getting it messed up.
Pro Many, many integrations
For example from Emacs, Sublime Text and so on. You can learn about integrations here.
Pro Easy create diagrams from text
There is even a Visual Basic Macro to draw UML diagrams in Word.
Pro Free/libre/open source (GPL)
Source code can be browsed here.
Pro Has online editors
Pro sphinx-contrib extension for embedding into docs
Allows you to keep your UML definitions under VCS and include them inside generated documentation with ease.
Con Watermark on export for free users
If you are free users, exporting document will create watermark
Con Web version requires FLASH
Flash is known to have security flaws and use high resources
Con Dekstop version is commercial
If you want to use dekstop version, you need to pay $75.00/ user
Con The "plantUML-language" is a bit strange and hard to grasp for new people
Con Slow development due to it being mostly a one-man project
There’s been no recent contribution to the source forge project but from the administrator arnaud_roques. Future contribution might be difficult due to lacking code documentation.