What are some alternatives?
When comparing Fastnative and PhoneGap, you can also consider the following products
AppPresser - Build iOS/Android apps using WordPress with AppPresser.
GoNative.io - Convert your existing web application into native Android and iOS
React Native - A framework for building native apps with React
Website 2 APK Builder - Convert your HTML, CSS, JS and all other web content into an Android App within seconds.
Bootstrap - Simple and flexible HTML, CSS, and JS for popular UI components and interactions