The latest docs have rudimentary support for Localization (everything is still in the DangerZone):
I’m interested in giving Expo’s solution a try, specially for it’s simplicity (versus, for example, this that was posted on Expo’s blog a few days ago: Translate your Expo (React Native) mobile application | by Jan Mühlemann | Exposition)
The problem is: I don’t see in the example code (in the localization page) any mention whatsoever to string interpolation. That’s a must have and basic feature for any LocaleStore. Is it still not done, or at least planned to be released shortly?