I've been diving into some rudimentary (very rudimentary, trust me) iOS coding lately, and as soon as I picked up an iPad, one of the first thoughts that occurred to me was the idea of having a version of Xcode (the IDE that Mac and iOS developers use to make their apps) available for the platform. There are plenty of text editors available, and even some designed to actually write code on Apple's tablet. But I haven't seen a way to actually run that code -- until now, that is, with Codify.
To be clear, Codify isn't a Cocoa development tool like Xcode, so you still can't write and run iOS apps right on the device (though I have to believe Apple is indeed working on some sort of Xcode for iPad, somewhere in the bowels of Cupertino, right?). But it is a development environment for Lua, a lightweight and simple object-oriented programming language used in all sorts of places. You can basically write and run Lua right inside Codify, which gives you a very powerful tool for creating your own small apps, prototypes and games right there on the iPad.
There are a few advantages and drawbacks to this. The advantage here is that the iPad of course uses a touch interface, so Codify has really smartly invoked touch in a few different ways while you're coding. To see coordinates or colors, for example, you can just drag your finger around on the screen. And you can scroll right through your code, your objects, or Lua's documentation just like browsing through anything else on your iPad. While I'm not hugely familiar with Lua (yet), the whole experience seems really great, and should hopefully convince other app makers to start looking at using iPads in this way more.
The biggest drawback, however, is that as far as I can tell, there's no real way to get your code out of the app, other than just cutting and pasting it off to email or somewhere else. There's also no (official) way to get other files like sprites and sounds into the app, though the FAQ says that's being worked on. These are more obviously issues with the iPad and iOS itself, of course, rather than the app, though it would be nice at least to see FTP or Dropbox integration.
But I do like the idea of using my iPad for actually writing code. That bigger touchscreen just seems to encourage creativity, and while most code writing in the past has been the domain of the desktop, why shouldn't there be apps designed to bring code and app creation to more and more people with simpler and better tools? Codify is a great first step in that direction -- it's $7.99 on the App Store right now.