Android app is on our roadmap. This app was the first step toward amazing Prismatic clients for different screen sizes and platforms. We have a couple of big changes to the core product before we become ubiquity focused.
I'm so sorry we teased you guys for so long but you have to admit some of our buzz videos were enjoyable. :-)https://vimeo.com/47600364
We hope the wait was worth it.
Hardest and most rewarding was all the serious engineering we did to make the app and gestures fun and fast. Most of the components in the app are custom, from the navigation controller to the story menu down to the scroll physics. Aria just answered this Quora question that goes into some of the details.