I recently decided to give React Native a go, and made a clean & simple Hacker News app. I've also open sourced the code at https://github.com/G2Jose/ReactNative-HackerNews
I was really impressed with how easy it was to get started, and build an actual cross platform native app using tools & language I already know (JS).
I've published the iOS version of the app at https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftw...
I'd love to hear your thoughts!