This past week brought us the unveiling of the Amazon app store for Android apps and as it enables people to make purchases both from their smartphones and their PCs (to deliver to their smartphones) this opens up some very interesting capabilities. One of the more interesting features that comes along with the app store happens to be a blank slate, virtual Android OS that enables potential buyers to test-drive the app to try before they buy on the web.

You can find the “TEST DRIVE NOW” button on the purchase screen—it’s huge, green and quite obvious. I went in and decided to give it a spin and tried out a video game that I rather enjoy: Bubble Buster. Needless to say, it’s playable and I even won a round.

According to Amazon.com the technology behind the test drive interface is also quite impressive,

Clicking the “Test drive now” button launches a copy of this app on Amazon Elastic Compute Cloud (EC2), a web service that provides on-demand compute capacity in the cloud for developers. When you click on the simulated phone using your mouse, we send those inputs over the Internet to the app running on Amazon EC2 – just like your mobile device would send a finger tap to the app. Our servers then send the video and audio output from the app back to your computer. All this happens in real time, allowing you to explore the features of the app as if it were running on your mobile device.

Mouse controls do seem to be enabled as well—I was able to move the pointer around by holding down the mouse button at first and double-tap fired. I am suddenly tempted to check and see if Angry Birds Rio is available via the test drive interface (doesn’t seem to be the case yet)—it debuted with much fanfare alongside the Amazon Appstore itself.

We’ve seen Amazon really come to the field with their Appstore with a great deal of gusto. They put the word out early, garnering notable support from the developer community as quickly as possible. To the extent that they pulled in quite a few big names the moment they went to market from Angry Birds to applications like Pageonce.

The way that the test-drive technology works according to Amazon.com makes me wonder if Amazon might start selling EC2 space for people to export the virtual machines of people’s smartphones so that they can also access them from their computers. In fact, it would be useful for people to upload the state of their phone, then use update it from their computer before updating it. When it comes to the interaction of a constellation of apps, that could be quite useful.

The very fact that Android is easily virtualized and its input/output can be streamed through a web plug-in makes for a lot of interesting applications.