Firefox OS: Hello World
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> <html> <head> <title>First App</title> </head> <body> <h1>Hello World</h1> </body> </html>
- 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")
 

- 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!
