This is why antitrust laws exist - sometimes the market realities make this nearly impossible.
The feature/capability parity between the platforms means they are, in fact, both capable of serving these markets. But people want to vote with their dollars in the iOS ecosystem, and now the players want to change that ecosystem.
I'm not entirely convinced that this is Apple's problem, in as much as it is Google's fault for not fostering a properly competitive revenue delivery platform, even though it has the maturity and standing to do so.
Also for some serivces iOs users are the large majority, like more or less any "real premium" service (Like apps you have to pay 10 or so+$ a month or 100+$ when buying them).
Anti trust laws (or competition laws) tend to apply to players with an clear control over the market, monopolies that stifle competition. Apple has ~14% of the mobile market, compared to Android's ~86%. I'm curious about how this will play out as it might have an impact in other sectors where smaller players by market share exercise a bit too tight control.
Don't know about tablets, but I feel it's not different.