RubyMotion is a tool that allows developers to build native iOS apps using Ruby. It uses Ruby code but generates native ARM code, allowing apps built with RubyMotion to be deployed to the App Store. RubyMotion provides access to the full iOS SDK and Objective-C runtime from Ruby. While it has some limitations like the inability to use "require" and regular Ruby gems, RubyMotion allows developers to code iOS apps faster in a familiar Ruby environment. The future of RubyMotion looks promising with its growing community and capabilities like providing DSLs for common tasks.