Hook VPN
Hook VPN is virtual private network app for Android. It includes in app purchases ( at least for the version on the Google Play store ). There is also apparently an app with the same name but from a different publisher on the Apple iOS app store.
This seems to be a relatively popular app so far. It has over 500K downloads on Google Play and comes up in searches on other alternative app stores. The search volume for this app is somewhat high as well.