Mozilla wants software application developers to regard its Firefox family not just for its obvious browser connections, but also for the Firefox OS operating system.
Mozilla's sales patter for this new OS is "Firefox OS for developers: the platform HTML5 deserves".
The firm is currently tag-teaming with friends like Dan Appelquist, who is an open web advocate from Telefónica Digital / W3C, and Mozilla's own principal developer evangelist Christian Heilmann — the two are trying to explain and clarify how developers can extend the functionality of HTML5 apps without having to access the phone hardware on behalf of the user.
Web Activities are a way to extend the functionality of HTML5 apps without having to access the hardware on behalf of the user. In other words, you don't need to ask the user to access the camera or the phone, but instead your app asks for an image or initiates a call and the user then picks the app most appropriate for the task.
So for example, in the case of a photo, the user might pick it from the gallery, the wallpapers, or shoot a new photo with the camera app — and then get the photo back as a file blob.
According to Mozilla, "Firefox OS is currently under heavy development; we are constantly working on ways to make it easier for you to use and hack on Gaia (the default set of apps) and create your own. However, you need knowledge about systems in order to do things like build the entire Firefox OS stack, or flash a phone with a build of Firefox OS."