app_delegate.rb

class AppDelegate
  def application(application, didFinishLaunchingWithOptions:launchOptions)
    true
  end
end

environment.yaml

hoge: foo

Gemfile

source 'https://rubygems.org'

gem 'rake'
# Add your dependencies here:

gem 'motion-my_env'

Rakefile

# -*- coding: utf-8 -*-
$:.unshift("/Library/RubyMotion/lib")
require 'motion/project/template/ios'

begin
  require 'bundler'
  Bundler.require
rescue LoadError
end

Motion::Project::App.setup do |app|
  # Use `rake config' to see complete project settings.
  app.name = 'myenv'
  app.my_env.file = './config/environment.yaml'
end