How are companion Apps charged?

I have a subscription website that I wish to have a companion app for

Both Apple and Google charge 30%

But how does it work if the app is a part of a paid service?

In other words, people will pay for use of a website and also receive apps as part of the subscription.

Tiered pricing as per number of users, each user needs an app

However there is no way of knowing whether they will have 6 Android and 4 IOS, or whatever... So there is no way to simply pay 30%

To give you an idea They would pay 49.95 for the site + 5 users and 99.95 for the site + 10 users and 149.95 for the site + up to 100 users

How would this be done for Google and Apple as far as the store charges?

It would be similar to numerous apps I have as part of a paid service, such as my Xfinity, I could not have a usable app were I not paying Xfinity, but I can't imagine Apple is collecting 30% of my Xfinity subscription. Same with a company that serves the car sales business. The dealership pays a monthly fee for calenders sent to all their clients, each sales person has an app for submission, but there is no way Apple & Google are each collecting 30% on these apps.

If for no other reason that there is no way to know from one month to the next (due to employee turn over) how many of each operating system there will be?

How are companion Apps charged?
 
 
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