Today, the Firefox OS team launched Firefox OS Simulator. It is a Firefox add-on to run on Mac, Linux and Windows.
After the installation is done the OS simulator will automatically keep updates with the latest snapshots from the Boot to Gecko (B2G) project. This is meant for those developers who want to work on apps for the new system, and don't mind using an obsolete version. The Firefox OS Simulator is the easiest way to try out Firefox OS apps.
Unlike other simulators, Mozilla confirms that the Firefox OS Simulator does not create a virtual computer, but instead the add-on essentially brings B2G Desktop, a version of the operating system-to the browser.
Mozilla expects to release version 1.0 of the simulator very early. At present it is version 0.7. The main object the team envisages by its version 1.0 is to make it simple to run B2G and install apps that one is working on.
If you are a developer, you can have a look to the updates through Firefox OS Simulator, and also share some usefulness of it here in the below comment section.