How to test chrome app and extensions in chrome book running chrome os?

Transfer your app code to Chrome book via Google Drive or USB
Install the chrome-dev-editor editor from Google Web Store

https://chrome.google.com/webstore/detail/chrome-dev-editor/pnoffddplpippgcfjdhbmhkofpnaalpg

Open the project in the chrome dev editor
Select the project and Click the Play button on top left corner. It will launch your application.
Now, you can go to chrome://extensions/ and launch the dev tools for that application.

Happy Developing Chrome Apps !

chrome apps 6 google chrome os 2