I know you can do it for iPad, and now also for Amazon. But what about for Google? Can the Viewer Builder create an app that can handle subscriptions for that marketplace?
You can set up in-app billing for selling individual folios, but Google Play (formerly Android Market) doesn't have subscription options, unlike Apple and Amazon. You would need to set up a custom entitlement server using an Enterprise account to set up a subscription. Here's info on publishing to Android/Amazon:
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