ReactiveCocoa is an amazing system, and RubyMotion could benefit from the lessons learned there! Motion-Wiretap is, essentially, a wrapper for Key-Value coding and observation. It exposes a +Wiretap+ class that you can use as a signal, or add listeners to it. Extensions are provided to listen to an +Array+ of +Wiretap+ objects, and the `UIKit`/`AppKit` classes are augmented to provide actions as events (gestures, mouse events, value changes).
Full article: http://rubygems.org/gems/motion-wiretap