When I worked at General Mills, I started by making mobile applications with the hybrid framework Sencha Touch. I found it very easy to use and make apps. A few years later I heard about Ionic, another hybrid framework. For my first app using Ionic I created a simple game that recreates Celebrity on the phone. You can download it on Android or Apple.
Ionic was easy to use, and I think it's a great candidate for prototyping apps. In my spare time I have actually used it to create early prototypes for our games at TableTapp. While it's easy to use, there is still some performance issues, which is why we are planning to move to React Native to get better performance.