Huge time saver

I tried online tools, i downloaded and tried a couple of competitors from the app store but this is the tool I use to help me develop, refine and debug RegExs.
It is focused on helping you get the job done without trying to be cute or flashy.
Features I like :
• accuracy, if it works in RegEx it has always worked the same way in my Perl script
• color coding in the match expression it makes it more readable.
• ability to paste in large ammonts of source text.
• ability to save out the pattern & source text you are working on so you can return to them later.
• colour coded match list which shows what will end up in your $1. $2 etc capture groups.
• click on match takes you to the match in the source text
• clean drop down for syntax hints

What doesnt it do
It doesnt show invisible characters in the source text - at least if it does I havent been able to work out how.

Alan-Laidlaw about RegExRX