In this edition of Firefox, the developer tools are front and center. To the right of the address and search bar is a wrench icon that will lead you to all of the various tools available. Many of these are already available in the basic Firefox package, but Developer Edition introduces two brand-new ones: WebIDE, and Valence. WebIDE, as it sounds, is an IDE for developing apps from right inside of the browser. You’ll be able to launch an app in its own window, and adjust its code on-the-fly. This will be especially useful to those building apps or websites for mobile devices, since the aspect ratio and orientation will match what most people will see. Valence, formerly known as Firefox Tools Adapter, connects the Developer Tools to other browser engines, including mobile. Continue reading this story here.