Using Rhomobile as API only with React Native Frontend

Hi,

Now it is impossible.
It is possible theoretically but require a lot of changes and refactoring in both solutions.
Also I think it is bad way because ReactNative's strong point is integration UI components with logic/data based on React architecture and strong point of Rhodes is hybrid architecture with UI based on WebView.

Now you can use native UI in Rhodes application by implement native extension based on our NativeView API.
You can find complete example in our Rhodes-System-Api-Samples application : github.com/tauplatform/rhodes-system-api-samples/tree/master/app/NativeView
And extensions with NativeView for iOS/Android/WM located : github.com/tauplatform/rhodes-system-api-samples/tree/master/extensions/rainbow