This is cool. I have been building an app in RubyMotion and the REPL has been pretty useful.<p>That said, at least for me, the REPL is a bit overhyped. In most cases the stuff you will tweak with the REPL is UI stuff. But the thing is if you are using IB and designing your screens in Photoshop or Sketch, the UI should be pretty much in place before it hits the code.<p>As far as other use-cases beyond UI, if you are doing any other type of "testing" in the REPL, you probably should be writing unit tests :)