Facebook’s solution is an open-source project called React Native that builds on its successful React project for Web development. Facebook claims that React Native will let the same set of engineers build applications in the same way for either iOS or Android. This time the company has set its sights a little more realistically than it did with HTML5. React Native is a learn-once-run-everywhere (LORE) app development tool.
I find it odd that a majority of the articles and documentation about React Native fail to mention upfront that Android development isn't available yet. While this article does mention that fact, it seems weird to me to push a cross-platform solution when only one platform is available.