What would be the best approach to translate an app?

currently if you update locale, you get always the default language not the language you selected on the upload

Yes, that's just an App Loader issue which I've got down to fix.

But yes, if we did replace on upload then we'd have to have the App loader be able to figure out what the current language is set to. For now, it seems that if we could handle translation with the Locale/Language app that'd be preferable - that's one of the things it was intended for after all