PUBLIC MARKS from Spone with tag debug

The free web debugging proxy for any browser, system or platform

Regex101.com is a free of charge service where you can create, test and have your regular expressions explained. Thanks to the permalink feature, it is a great reference which may even be used in code where you need to explain your regular expressions to co-workers.

It's a debugger for web pages, like FireBug (for FireFox) and Web Inspector (for WebKit-based browsers), except it's designed to work remotely, and in particular, to allow you debug web pages on a mobile device such as a phone.

Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet. This includes requests, responses and the HTTP headers (which contain the cookies and caching information).

The Scienta Debug Bar is a plugin for the Zend Framework for PHP5. It provides useful debug information displayed in a small bar at the bottom of every page. Time spent, memory usage and number of database queries are presented at a glance. Additionally, included files, a listing of available view variables and the complete SQL command of all queries are shown in separate panels.