If you haven't seen it already, go check out Ars Technica's massive "history of Android" article,* covering everything from the earliest public release candidates all the way to KitKat. More than a simple collection of home screen shots, they go in-depth on changes, design philosophy, abandoned apps and missteps, and long-term triumphs of Android. I'm only about halfway through (it's 26 pages) but definitely worth a read if you're a tech history buff, a fun walk down Android memory lane.
* I recognize that AC sometimes frowns on promoting other websites' posts, but this one is so interesting I wanted to make sure others saw it.
* I recognize that AC sometimes frowns on promoting other websites' posts, but this one is so interesting I wanted to make sure others saw it.