I hope you know what's Spotify's complaints these few years. For your convenience:
Apple turned down a new version of the app while citing “business model rules” and demanded that Spotify use Apple’s billing system if “Spotify wants to use the app to acquire new customers and sell subscriptions.”
In Spotify’s case, the company has used Apple’s billing system for years, but passed on Apple’s fee to customers by charging $13 a month instead of the $10 a month the service sells for outside Apple’s store. Last year, after Apple launched its own music service,
Spotify became more vocal about encouraging users to pay for the service outside of iTunes.
Last fall, Spotify started a new end-run via a promotional campaign offering new subscribers the chance to get three months of the service for $0.99 — if they signed up via Spotify’s own site. This month, Spotify revived the campaign, but Gutierrez says Apple threatened to remove the app from its store unless Spotify stopped telling iPhone users about the promotion.
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Apple is providing their secured billing, engineers to maintain the app store, support service blah blah. Yes, some people like you may think Apple is not justified to earn $3 of the $13. Then don't use iPhone.
FACT ONE: Spotify has control over their pricing.
FACT TWO: Spotify can decide ditching iPhones
FACT THREE: Consumers can ditch iPhone is Spotify is such an important part of their lives.
Why complain about Apple earning that $3 if you as consumers and Spotify, as developers have their choices