Amazon's Mac download store even has some software that Apple's doesn't, such as Microsoft's Office suite.
The growing rivalry between Apple and Amazon is going to get interesting.
Like Apple's relationship with Google, the companies rely on each other in some areas -- Amazon sells a lot of iPods, Macs, etc. -- but increasingly compete in others. Amazon is said to be getting into the tablet market, where it could give Apple some real competition, and the Kindle e-book store competes with Apple's iBookstore on iOS devices.
We're especially curious how Apple is going to enforce new payment rules on Amazon's Kindle app -- will it really try to force Amazon to sell all Kindle books through iTunes, and give Apple a 30% cut of sales?
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