Can anyone concisely explain what this fine is for, and also why the same wouldn't apply to Apple for iOS? It seems to be a rehash of the issue that Microsoft faced when it only gave you Internet Explorer on install. But iOS comes with only Safari on install, and forces you to use Apple's various apps - how is this any different?
Apple does not have a dominant market position and does not give away iOS for free.
Making Android free is an anti-competitive practice because it inhibits the formation of a competitive market for mobile phone operating systems. Because Google's practice of making Android free inhibits competition they are not allowed to exploit the lack of competition for profit.