Does Katalon support all of possible keywords for WebUI / API / Desktop / Mobile testing?

The Katalon development team always try their best to implement all of considerable keywords for all kinds of testing that we have. Nevertheless, we can't cover all of specific cases or scenarios of users. Therefore, Katalon team supports Custom Keywords. This means that users can create keywords for their own by themselves. 

For more details about how to create a custom keyword, please refer to this guide for more details https://docs.katalon.com/katalon-store/docs/publisher/develop-custom-keywords.html#develop-a-custom-keywords-plugin