Phantomas : PhantomJS-based web performance metrics collector and monitoring tool
Squoosh : Squoosh is an image compression web app that allows you to dive into the advanced options provided by various image compressors.
Browser Calories : The easiest way to measure your performance budget.
Skipfish : Skipfish is an active web application security reconnaissance tool. It prepares an interactive sitemap for the targeted site by carrying out a recursi...
Crosswalk : Include the Crosswalk Project web runtime with your hybrid Android or Cordova / PhoneGap app, and users will consistently see it through a predictable...
The Web Developer extension adds various web developer tools to a browser. The extension is available for Chrome, Firefox and Opera, and will run on any platform that these browsers support including Windows, OS X and Linux.