I'm gearing up to build my first mobile app in 2018 and am looking for some high level advice on which technologies to use, ideally from someone who has used them and had success developing and deploying a production level mobile app to both of the major app stores (android and iOS).

Without giving away too many details, the app is geared toward consumers and will consist of a companion web application, which may or may not have the same feature set (TBD).

I'm thinking of developing one or more RESTful APIs to do the heavy lifting, leaving me with the UX/UI for the different platforms.

I'm looking for advice on which code-once technology I should use (Xamarin, Cordova, etc) so I don't have to make both an objective-C and Java variant. Keep in mind, that if my market shakes out and the app goes into growth mode, I'll need more than just a UI layer, so I don't want to get invested in a technology that limits my options down the road.

Lastly, the app is essentially a series of screens and forms for data collection, presentation with various media elements thrown in from time to time. It's not a game and doesn't need to make use of device hardware, but the ability to leverage device APIs for location, basic user info, etc will likely be needed.

NOTE I'm asking this here because I am a seasoned dotnet developer who would prefer to embark on this new adventure using familiar tools (Visual Studio, C#, etc). I'm inclined to use Xamarin but I'm not sure it is the best option.