I would recommend taking a look at Litho (Android) and ComponentKit (iOS). Both frameworks by Facebook and inspired by the React component model for pure native development.
Do they plan on unifying them into one framework, or are the platforms different enough that they've given up on having one framework to do everything?
Litho and ComponentKit have similar APIs and we try to bring them closer together, but I'm not sure what unifying them would actually look like. You would still end up with two libraries that target very different languages. React Native is there to stay if sharing logic is more important to you than raw speed.
Ah okay, so they share the basic programming ideology but each is a bit more tailored to their target platform. Is that right? The advantage then being that it's easier to write versions for Litho and ComponenentKit than it is to write Java/Kotlin and Objective-C/Swift versions.