I dont really understand why people are in love with React Native. Looking at this example code it looks pretty gross (In my opinion) compared to doing the exact same thing in Obj C or Swift.
Agreed that still react-native is far to give you complete solution but the future looks promising.
React Native is great for building applications with the desire to have them run cross platform while using most of the same business logic/views. Should you use React Native for everything? Hell no.
You do get css styling, flexbox layout, can greatly lessen the build and maintenance costs of an app, leverage current React knowledge, and very easily bridge to the native world with React Native.