What are some alternatives?
When comparing Fastnative and Website 2 APK Builder, 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
appenguin - Turn the most complex web application or website to into an Android app in minutes, for free!
AppInduce - The Next Generation DIY App Builder
Andromo - Android app maker software.