This gist's comment stream is a collection of webdev apps for OS X. Feel free to add links to apps you like, just make sure you add some context to what it does — either from the creator's website or your own thoughts.
The best code editor for Mac, and a definite must have.
##Transmit
Excellent FTP app, used by Coda for years
##Codekit
CodeKit helps you build websites faster and better. Its flagship features are listed [on the website] and the one-minute teaser video is a good place to start.
##Tower
GUI interface for Git, works with Beanstalk
"MAMP PRO" is the commercial, professional grade version of the classic local server environment for Mac OS X: MAMP. Designed for professional web developers and programmers, MAMP PRO allows easy installation and administration of their development environment under Mac OS X.
MAMP is free and Pro is cheap. The only thing the Pro version gives you is a GUI for things you could have already done yourself via command-line fu. I use Pro for its convenience.
##Mixture
The best tool for creating the initial static site, a must have also.
##Patterns
A simple yet powerful tool for working with regular expressions. - * optional Build great patterns quickly and effortlessly with syntax coloring and with matching and replacing occurring in real time.
Sequel Pro is a fast, easy-to-use Mac database management application for working with MySQL databases.
##Homebrew
The missing package manager for OS X
1Password can create strong, unique passwords for you, remember them, and restore them, all directly in your web browser.
##Mou
The missing Markdown editor for web developers
##Gradient
CSS gradient generator, can output SCSS and Compass compatible code - * optional
Network monitor - * optional
##Dash
Dash is an API Documentation Browser and Code Snippet Manager. Dash stores snippets of code and searches iOS, Mac, Man Pages and custom docsets. - * optional