I'm on the fence about this and RubyMotion in general. By far the most time consuming part of app development is getting the visuals and animations looking right, and I don't see how this helps. The basic scaffolding (setting up view controllers, transitions and talking to the backend) is the easy bit.
On the other hand, I'm a Python guy and I've never fallen for Objective-C (although recent sugary additions have made it far more pleasant).
Visuals and animations are infinitely easier to get "looking right" when you can modify parameters directly in a running app via REPL. That's possible with RubyMotion. In particular, check out https://github.com/rubymotion/sugarcube#repl-view-adjustment... .
I second this. I demoed the Sugarcube repl for our mobile team (I'm primarily a JavaScript dev who has fallen in love with RM) and everyone was universally blown away. It's the most useful thing ever -- well that, combined with Teacup.
On the other hand, I'm a Python guy and I've never fallen for Objective-C (although recent sugary additions have made it far more pleasant).
Can anyone who has made the jump enlighten me?