An Android version will launch a few months later, likely by May 2013.
But it sounds like Office for Android and iOS will be a watered down version of the apps on Microsoft's mobile devices. You'll only be able to view documents with the free version, not edit them.
If you want to edit documents, you'll have to purchase a subscription to Microsoft's Office 365 service. But even then, you only get basic editing features. Warren reports that it won't be a full version of Office.
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