Example to use UIWebView for RubyMotion.

app_delegate.rb

class AppDelegate
  def application(application, didFinishLaunchingWithOptions:launchOptions)
    @window = UIWindow.alloc.initWithFrame UIScreen.mainScreen.bounds
    @window.rootViewController = GoogleViewController.alloc.init
    @window.makeKeyAndVisible
    true
  end
end

google_view_controller.rb

class GoogleViewController < UIViewController
  def viewDidLoad
    self.view = UIWebView.alloc.init
    url = NSURL.URLWithString("http://www.google.co.jp/")
    request = NSURLRequest.requestWithURL(url)
    self.view.loadRequest request
  end
end