Since the custom mobile app is generated under your label and brand, it also needs to work with some of your service providers, such as a Google Firebase Messaging (GFM) key to enable push notifications, or AWS S3 credentials to store user-generated assets.
As you can imagine, some of these settings are required for the application to work properly and some can fallback to the default iWelcome Authenticator settings.
The generated mobile app will still work with the iWelcome Authenticator API and back-end, so you don't really have to worry about an additional service to keep online and manage. The target result is to generate your custom mobile app and either distribute it or resell it under your own brand and image.
Once you've created a custom mobile app, its package id(or bundle id) and app name cannot be changed and will be used to create your monthly subscription.