I know there's been a thread about this already, but as far as I know it's about four years old. Just curious, what IDE do you use for development (specifically for XenForo add-ons, but PHP in general)? Reply with your reasons why if you wish. Some major ones are in the poll. Here are some interesting statistics from a poll of 4000 legitimate people. I believe PHP Storm is used for developing XenForo (by Mike, Kier etc), and I think they used to use Zend Studio before that. Not 100% sure though. I am currently using a trial of PHP Storm, will most likely purchase it near the end of my trial (when I get a new laptop, it's on the way). It's mainly because I used Intellij IDEA back when I was doing Java programming, and I really loved the interface.