Having a familiarity with the underlying development paradigms of a CMS is one of the key evaluation factors. In this respect, ASP.NET MVC should be on your radar because the framework is established as one of the best and there is a ton of information available about it. Also, using a strongly typed language as C# is easy and fun.
NativeScript makes it easy to get native performance on mobile apps. Just ask SAP, whose enterprise app modeler relies on NativeScript for peak performance.