精通就有用。即使是non RAD. But it need fast. Make the dev fast, i believe it will be useful. 话说你用swift, 测试用啥?有啥推荐? 另外,我做了FB上的chatbot用的FB的SDK, 感脚不顺畅,如果现在或将来有心得在chatbot on social app such as FB or Whatsapp, 推荐给我。