Back in October, we posted a quick look at some of Google's very early plans for multi-window functionality on Android Lollipop, a feature that had apparently been in the works since at least KitKat. The system, in a nut shell, would allow users to have two apps open at a time, scaling the apps to take up more or less space on the screen, and interact with the overview or Google Search, passing text or other data back and forth.
As a developer, I absolutely love days like today. If the high-level "improves performance and stability and fixes bugs" changelog of Android 4.1.2 isn't good enough for you, how about we dive into the actual low-level source code commit logs Android engineers made into AOSP since 4.1.1_r1.1 (JRO03D) all the way through today's release 4.1.2_r1 (JZO54K).
Multi-user support is one of the few remaining things a desktop OS can do that Android can't. The "coffee table tablet" use case would greatly benefit from a multi-user setup, as would an enterprise user who wants to keep work and home separate. It's been a top 20 item on the Android bug tracker since the debut of Honeycomb, so there is certainly demand for it.
Have you ever wondered what the AOSP source tree would look like if someone stitched together a video of every commit, update, and release? Ponder no more, friends, because YouTube user xcco3x has made that a reality. A visually amazing 21 minute reality, to be exact.
A little background info, per the description on YouTube: