React native localizations: Global variable

I am new to React, and I come from the world of iOS/Android where localized strings are all defined in dedicated files. I have looked into react-native-localization and it seems like we need to define the strings object in each class and then use the values in the rendering. This seems to be quite inefficient and fragmented to me, or maybe I have misunderstood the usage. I haven't been able to find good examples of the usage of react-native-localization. I'd really appreciate some guidance.