1. wait to see if cloud based gaming catches on, and move on that market, maybe together with trying to control the TV.
2. online banking/insurance services(maybe?). uses cloud + trust + credit cards. Those are industries are on a verge of disruption to a much more efficient and automated model, need complex automation, and are consumer facing.
3. Control the e-book distribution market worldwide,
4, Get a larger part of the content creation ecosystem(movies, publishers, maybe music or educational content)
5. An online advertising move using the kindle fire silk browser and amazon browsing history. They would combine that with their general retail savvy to create highly effective service
6. Groupon like service - have a cut of every local commerce transaction. Again superior customer knowledge helps recommend offers, and they could find a way to advertise to small business owners in their site.
But their main goal is :
Sell move stuff , more groceries / CPG and more heavier stuff. They could do all this based on the success of prime and new logistics build for it.
Amazon's foray into mobile is "just" a natural extension of their retail business. The primary purpose of the Kindle and their variety of mobile apps/services is to get consumers to buy digital goods from Amazon; just as Amazon (the retail) is to get consumers to buy physical goods. The logistics plays a large role in keeping the physical goods flowing; AWS gives them a solid platform to keep the digital goods flowing.
But the interesting thing is, I think, how Amazon realised that building a superior delivery network for bits would be just as much of an advantage as having a superior delivery mechanism for atoms was. You buy a kindle from them. Amazon ship it to you. You turn it on, buy things, and the bits just arrive. And Amazon have that process down better than anybody, even Apple.
There are synergies here I'm fairly certain I don't understand -- I look forward to seeing what Amazon can do over the next 5-10 years.