While these magazine apps are often free on the iPad and iPhone, purchasing the actual issues costs extra.

尽管在iPad和iPhone上这些电子杂志通常是免费的，购买真实期刊才额外收费。

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You can even read both books (thanks to free apps from Amazon) on your iPad, iPhone, Android, Mac or PC.

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It was just last October that Apple allowed in-app purchases for free apps, effectively allowing for sales of virtual goods on the iPhone.

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Ford has done well to encourage developers to tailor their services for Ford SYNC, courting them by releasing a free API, and maintaining the apps fundamentally just need to run on the iPhone.

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