Ruby on the iPad

by James

Since I wrote Thoughts on the iPad yesterday, that article has been getting lots of hits from people searching for “ruby on ipad” — or variations thereof.

If you’ve reached this post by searching for something similar, I’m guessing you want to do one of two things: either 1) run Ruby on an iPad, or 2) develop for the iPad using Ruby.

1) Run Ruby on the iPad

Never going to happen.

Like the iPod and the iPhone, the iPad is a closed system. The only near-possible way to run Ruby on an iPad would, I’m guessing, be to create an app which bundled Ruby and provided a command-line interface to it. But that’s not going to happen either. Can you imagine Apple approving an app which allowed users to run any code they liked — even within a sandbox? Neither can I.

2) Develop for the iPad using Ruby

This is less clear-cut: there’s obviously no support for Ruby in the Objective-C iPad SDK, but we do have MacRuby: “a version of Ruby 1.9, ported to run directly on top of Mac OS X core technologies”. I think the key words there are “Mac OS X technologies (my emphasis)”; Mac OS X is different to iPhone/iPad OS X, and right now there’s about as much chance of using MacRuby to develop iPad apps as there is of Bill Gates coming to work at Apple.

That might change though (the MacRuby thing, not Bill Gates) — which change would depend on MacRuby becoming a popular way to develop for the Mac. If enough developers use it, Apple may — may — decide it’s worth their time an effort to port MacRuby to their other platforms.

So, Googler: there’s some small hope.