DOMScope
Chrome DevTools
Firefox Developer Tools
Browsersync
Ghostlab
SplineTech Javascript Debugger
Muir
Code Cola
Vim Python IDE
DOMScope
Vim Python IDENo features have been listed yet.
Chrome DevTools - Get started with Google Chrome's built-in web developer tools.
Firefox Developer Tools - Examine, edit, and debug HTML, CSS, and JavaScript on the desktop and on mobile.
Browsersync - Browsersync makes your tweaking and testing faster by synchronising file changes and interactions...
Ghostlab - Ghostlab allows you to test out a newly developed website on a variety of browsers and mobile devices at the same time. To get started, simply drag the web address to the Ghostlab system and press the play button. Read more about Ghostlab.
SplineTech Javascript Debugger - SplineTech JavaScript Debugger. Debug JavaScript.
Muir - Muir is a mobile browser testing app without all the strings of cloud based suites.