Use it to test your apps in a Firefox OS-like environment that looks and feels like a mobile phone. After installing it, go to Web Developer > Firefox OS Simulator to access its features.

Note: This download is an add-on for Firefox (only works with Firefox 16.0 and later) so we suggest you download this file which is a .xpi using that browser.

Download Key:

  • Windows = Windows Final version 4.0.1
  • Mac = Mac Final version 4.0.1
  • Linux = Linux preview version 3.0

What's New:

  • Push to Device
  • Rotation simulation
  • Basic geolocation API simulation
  • Manifest validation
  • Stability fixes for installation and updates to apps
  • Newer versions of the Firefox rendering engine and Gaia (the UI for Firefox OS)

Since then, apart from verifying and making the above functionality stable, other notable improvements are:

  • Keyboard shortcut to repackage/reinstall/restart the current app – drastically improving workflow speed, especially for packaged apps
  • Significantly reduced download/installation size of the Firefox OS Simulator
  • Faster start time (partly due to above with smaller size)
  • Much newer versions of Firefox OS and Gaia
  • General bug fixes, making it more functional and reliable
  • OS-standard ways in the menu to close the Simulator, with corresponding keyboard shortcuts (Alt + F4 on Windows, Cmd + Q on Mac, Ctrl + Q on Linux)