I have an app that created by awesome React-native
and my layout designed to be in RTL mode. I\'ve set up an option for forcing the layout to be RT
Make sure that on iOS, next to having added all relevant RTL locales to your Xcode project (e.g. Arabic). You should also make sure that your .ipa contains .lproj folders for each locale. Otherwise iOS doesn't pick up on the supported languages.
This is a common issue in React Native projects where you don't typically write a lot of Swift/Obj-C code & most of the translations happen in JavaScript (apart maybe from some stuff in you Info.plist).