I saw a similar app a couple of days ago, but I had already installed Xamarin. This app is the preferred tool for mobile native app development. It uses business logic layers and data access across platforms. It is widely used to create applications for iOS, Windows, and Android. By the way, APPROPIO mobile app builder is developed in the Xamarin programming language. You can learn more about the features of the builder by going here http://theymakeapps.com/.