Intellij handles Javascript great. One advantage of AppCode is that the IDE smarts aren't limited to Objective C code but also includes JS code, which works well when I'm working on my WebView/JS-based projects. I haven't used RubyMine directly, but I would be surprised if it didn't have JS smarts like all their other IDEs. However, I would echo chrizel's comment that Intellij would be that one IDE to rule them all, at least in your case. Intellij has some Ruby plugins that worked well enough when I played around with Ruby a few years back, and the plugin is developed and maintained by JetBrains themselves.

We use the same core for JavaScript, HTML, CSS among all IDE's. They're often not available at the same time because we ship at different times. Otherwise all the same.

Are you saying that if I buy AppCode WebStorm would be redundant/unnecessary?

I believe you can download it and evaluate for 30 days. In your case, it may be more like 23 hours, but you still get to play.

I've had pretty good success with most basic JavaScript stuff, whether in a .js file or embedded in some server side template. Haven't tested it with more complex stuff though. I also concur with my siblings here that IntelliJ IDEA is my "one IDE to rule them all!".

If you install the JetBrains Python plugin into IDEA you get the same functionality as PyCharm, same with Ruby.

If I have pycharm - is it more or less the same when I install e.g. the Ruby plugin?

I believe only IntelliJ gets the other IDEs as plugins.

I don't know if this is true (I'm not disputing it), however AppCode has officially been recognized as the only IDE version that will ever be compatible with *.xcodeproj files. It's functionality is not 'plugin-able'.

You're right, though I think that AppCode is an unusual case; you can only use it on OS X, right? It is a completely different beast.

For IDEA, though, you can indeed get the same functionality of PHPStorm, PyCharm, etc, by simply using their respective plugins for IDEA. However, the plugins are sometimes behind the stand-alone IDEs, in terms of features.

The "one IDE to rule them all" is IntelliJ IDEA. You will get most functionality of the other IDEs via plugins: http://plugins.intellij.net/?idea

I use PyCharm for Python & some Javascript development. Works quite well although there could be improvements in the code inspection for javascript files.