C++ vs native implementation of iOS/android

Question

I'm developing an app for iOS and android that identifies songs. We have a matching engine in c++ that works well, but my question is about the rest of the app. We have a user interface design that allows the user to record, match and save, as well as share, edit, and see their recordings.
I'm not a coder - just a designer- and I'm getting conflicting advice about how to implement. One person wants to do the majority of the interface in c++ with just a thin native GUI skin, while the other says we should write in native IOS (swift) and Android and only have the engine in c++. The argument for c++ is it will be a single code base to maintain - it would include doing the sharing, storing history, displaying sonograms, etc. The argument against is that in fact it will not be easier to maintain, and will also create a lot of problems making calls, for example, between the interface and the sharing module.
Hope this is clear - it's a very hard thing for me to assess as ignorant as I am! Any advice would be greatly appreciated.

Answer 1

In my opinion, the way to go is to write the GUI the way it was meant to be. Native iOS/Android will yield a much better user experience and will allow you to use the platform latest and greatest way of implementing a UI.

Also, I am assuming that the engine will probably not be developped by the same people that develop the GUI itself, so the argument that it would be simpler to have a single code base doesn't really make sense.

Another solution could be to use Xamarin, so that you can consolidate iOS and Android development, while still having a common C++ engine.

Edit: Typo