I would normally post this question in the NetTalk Central forums, but they are offline right now.
In the NetTalk mBuild documentation it refers to Adobe PhoneGap Build
https://build.phonegap.com/ but if you visit the site you get the following:
Adobe has discontinued PhoneGap Build and ended investment in PhoneGap and Apache Cordova.
This website is no longer being updated.
and by following another link:
The PhoneGap Build service will be discontinued on October 1, 2020.
I guess I’ll be making a Progressive Web App. Or is there some other preferred way of creating Android apps using NetTalk? Fortunately my client is only using Android phones, so I don’t have the complication of having to support iPhones as well.