The difficult part of making an e-ink Android, or applying an e-ink display to a general-purpose platform is that the way screen-drawing is implemented has not been designed with e-ink in mind.
The display might either seem "flashy" because the full screen is blanked and drawn for every update, or the screen gets "muddy" because the graphics stack isn't keeping track of how many times a screen areas has been rewritten without being reset.
Page-at-a-time updates, like those between pages of a book, are the most compatible with how e-ink works.
I've got a rooted Nook ("simple touch"), it handles the redrawing remarkably well. I wouldn't call it production-ready, but the shadowing is small and it's more than usable. Available RAM is abysmal, but that's a separate problem.
The weirder part is how e.g. dragging an icon makes a greyscale-rainbow trail behind it as it redraws pixels. Panning through the app screens is also pretty crappy, and all the little animations are so over the top with a slow screen rate that the results are basically laughable. I wish there were a "never animate anything, ever, for any reason" switch I could flip :|
Wait, it gets worse: once you have basic updating working, you face having to modify a lot of UI widgets that, for example, use smooth-scrolling, which would muddy-up an e-ink display. You could start by nerfing a lot of animations in Android, but I'd bet you would still encounter implementations that are not as clean as to use up-to-date animation implementations.
You would have to size the job by looking at every standard widget's implementation and factoring out the parts of that implementation that are hostile toward e-ink.
After all the widgets are clean for e-ink, you then have to take a look at some user interactions: Dragging a "thumb" to scroll through a list might be quite tough to do well no matter how it is implemented.
The display might either seem "flashy" because the full screen is blanked and drawn for every update, or the screen gets "muddy" because the graphics stack isn't keeping track of how many times a screen areas has been rewritten without being reset.
Page-at-a-time updates, like those between pages of a book, are the most compatible with how e-ink works.