Right now Apple's Services Business consists of:

  - Apple Music
  - iCloud
  - App Store / iTunes / Apple Books
  - Apple Pay
  - Apple Care
  - Licensing (i.e. default Google search)
  - Apple News+

Coming later in the year:

  - Apple Arcade
  - Apple TV+
  - Apple Card

I'm expecting Apple Arcade to be a huge source of revenue which I'm eagerly awaiting for myself (and my kids) to get off the cesspool of scammy Dark UX IAP land mines that currently proliferates the App Store.

Apple attribute $10 ( or $20 I can't remember ) per Unit ( iPhone, iPad and Mac ) into Services for macOS, iOS, iPadOS, and Apple Map.

There is roughly $10 per user paid to Apple ( iPhone, iPad, Mac ) for using Google as default search engine. Last estimate were $9B. Before you ask the Active User and $9B don't align, Keep in mind this is users excluding China, where Google is not available.

And App Store purchase, that is the 30% cut Apple received.

These three item likely combined to be 80%+ of Apple Services Revenue. The rest are iCloud, Apple TV, Apple Music, Apple Card etc..

Besides the App Store: Apple Care, movies, books, audiobooks, Apple News+, Apple Pay.

Movies, iTunes, AppleTV sorts of stuff might count

App Store