Let The Buyer Compare: App Store vs. One Pass vs. Kindle Store
"Apple's iOS App Store isn't the only game in town for subscribed digital content. Here's a look at how the plans to court publishers' subscription content by Apple, Amazon's Kindle and Google's One Pass compare."
A nice comparison of current content subscription services, with the bottom line here being about subscriber data (as potentially applicable to advertisers). Right now, Amazon has a huge lead in subscription partners, and since the Kindle app works on many platforms, it will probably remain in the lead - for now. Let the best models prevail!
"Not everything that can be counted counts, and not everything that counts can be counted." Albert Einstein