Finally Apple is capitalising on its install base to sell more addons after sale. This offsets slowing hardware upgrade rates, although not sure if it is enough to offset iPad declines.
The narrative often heard is that if they want to shift to being a services company, Apple would need to dramatically change its org structure. I may be wrong, but no one has ever monetised consumers with recurring monthly revenue as successfully as Apple has (utility companies and mortgage brokers excluded!). And it didn't even need an org restructure!