I think you have to try PHPEd, it's free and Maguma Studio for PHP if you use class for your application. They have syntax highlighting and the important is, they are free
What is the best free PHP editor
sorry dear but PHPEd isnt free:
http://www.nusphere.com/products/phpadv.htm
TexPad ( http://www.textpad.com ) is not free, but the nag screen is occasional and there is no expiration date on the trial period. It does PHP (and other language) highlighting, and you can download free clip libraries as well as small app to make it a notepad replacement. It is even simple to write your own or modify somebody elses clip library to have your favorite functions a mouse click away.
Do a search on this site,
there's a whole bunch.
Its obviously personal preferance, but in my view PHP Edit http://www.phpedit.com is very good, another good one is - good old HTML Kit http://www.chami.com/html-kit/
both are 100% free and ideal for PHP
The new version of PHPEdit isn't free, but the older ones - which you could probably track down - are. PHPEdit is nice because it allows you to debug your code if you have php running on your local machine. The variable drop down list is a good feature too.
-jim
PHP Edit is free ! PHPEd is not free, they are different products from different companies. PHP Edit (the free one) is better that PHPEd anyway. :p
phpcoder2 (though hard to find)
or
context (free, through I got mine froma friend and wouldn't know where you can find it...
a month later
The trial version of PHPEd is free for 14days
and in this 14days you will see the differense between all the other editors...
use this link to evaluate PHPEd http://ww1.nusphere.com/web/registration_page.php
have fun...
http://www.fixedsys.com/context/
CONTEXT HERE!