Aside from the live reloading and being able to write in javascript as opposed to Swift/Java, the development paradigms of React is just better, IMO. The component-based design patterns and event-dispatching-based control flow just make so much more sense to me than the traditional Android/iOS way of doing things (I have experience in both the web and mobile). It's easier to test, easier to read/write, and easier to reason about. This is just opinion of course, others may not feel the same.