LiveReload - LiveReload 2 proudly presents… The Web Developer Wonderland. (a happy land where browsers don't need a Refresh button). CSS edits and image changes apply live. CoffeeScript, SASS, LESS and others just work.
Vidrio - Holographic screencasting app for Mac. Free for COVID-19
Browsersync - Browsersync makes your tweaking and testing faster by synchronising file changes and interactions...
Scrimba - Interactive coding screencasts created in an instant
CodeKit - CodeKit allows you to optimize the performance of your website by automatically and efficiently compiling a variety of popular languages.
GoRails - Ruby on Rails screencasts for Web Developers