What are some alternatives?
When comparing Fastnative and GoNative.io, you can also consider the following products
AppPresser - Build iOS/Android apps using WordPress with AppPresser.
appenguin - Turn the most complex web application or website to into an Android app in minutes, for free!
Website 2 APK Builder - Convert your HTML, CSS, JS and all other web content into an Android App within seconds.
Andromo - Android app maker software.
AppInduce - The Next Generation DIY App Builder