That may sound just an easy job. Surprisingly its not! Its because React Nativeis evolving at a very high speed. The community is vibrant and React itself is also moving at a very high speed. Though there are minimal API changes but there are changes and sometimes there are breaking changes. Well as for iOS, we know it also comes with API changes and sometimes breaking changes.
The absolute minimum one has to do, to maintain a React Native project on iOS is to check for all the tool chain is upto date. Being said that, there are dependent libraries and there are chances that these things may not sync and your project may break.
As of today React Native is 0.42 and to compile an iOS project, it seems the bare minimum is
The code reference to update the react-native-cli would be just to re-install it.
sudo npm install -g react-native-cliTo know the version of both, its as simple as this.
react-native --versionHopefully that opens up the idea as to maintaining a project is also a time consuming process. And with projects which evolve, if one has develop its own project, then the time and effort to maintain it will be exponential.
Happy Coding.