Apple v. Amazon

Both Apple and Amazon have demonstrated how a vital online marketplace can spur sales of mobile hardware. Apple, of course, has the iTunes, iBooks, and the App Store to deliver content to millions of iPhone, iPad, and iPod touch users. Amazon's Kindle ebook store has served the same role for its Kindle e-reader customers, and for those running the Kindle book-reading app on other devices.

With the launch of an Android app store, Amazon would be well-positioned to compete with Apple's iPad. In addition to offering Android apps and Kindle e-books, Amazon already has established and services. Amazon tablet users would have a wealth of content available from their hardware provider, a business model akin to the Apple ecosystem. (But unlike Apple iPad users, Amazon tablet customers could easily buy content elsewhere too.)

Today's Kindle is best suited for book-reading. It fulfills a niche that's distinct from that of the iPad and similar tablets, as Amazon CEO Jeff Bezos recently . And with the Kindle's price this year, a door is opening for an Amazon-branded iPad competitor with strong hooks into Amazon's collection of online content.

Amazon will unveil an Android-based slate. The only question is when.