Creating a HelloWorld app in firefox OS:

  • Make a folder “HelloWorld”
  • Create a text file in it, copy the code below into it and save the file as “index.html”
<!DOCTYPE html>
 <title>First App</title>
 <h1>Hello World</h1>
  • Create another text file in the folder and paste in the below and save that as “manifest.webapp”
 "name": "First App",
 "launch_path": "/index.html",
 "icons": { 
 "128": "/img/anna.png"
 "default_locale": "en"

Make sure you get your launch_path right!

  • Go to the app manager in firefox (Type into the URL bar in firefox “about:app-manager”)

Screenshot from 2014-02-06 23:30:46

  • In the apps sections click “Apps”
  • Click “Add Pacakaged App”
  • Open the folder “HelloWorld” where your index and manifest files are
  • Click the “Start Simulator” button at the bottom and pick the Simulator you want to use.
  • Click the “Update” button for your app to install it.
  • Click your app from the menu to run it

And voila!

Screenshot from 2014-02-06 22:39:05