MOUNTAIN VIEW, Calif.—With Google I/O comes a fresh version of the Android N Developer Preview—we're now up to Developer Preview 3. Google is calling this version of N its "first beta-quality candidate" and is encouraging a wider audience to try it out. Both OTA and image download should be available for the Nexus 6, 9, 5X, 6P, Nexus Player, Pixel C, and Android One (General Mobile 4G).

There are two headline features in this release. The first is a new VR platform, which we're covering in a separate article. The second will make for some great headlines: "Android copies Chrome OS update system!" But it's probably not what you're thinking. Yes, Chrome OS and Android are getting a little closer together, but Android is just borrowing the update installation method from Chrome OS, not the part where Google has full control over everything and delivers reliable updates.

Updates, once they are created by your OEM, approved by your carrier, and downloaded, will now be applied "seamlessly," just like on Chrome OS. You'll be on version 1.0, reboot, and you'll be quickly, transparently upgraded to version 2 without having to wait for any "Android is upgrading" dialog boxes.

Before the show, we chatted with Android VP of Engineering Dave Burke. "We were kind of inspired by how our Chromebooks work," Burke told Ars. "You get a completely seamless update. You don't do anything, you just turn on your Chromebook and it's up to date." Burke clarified that the Android team took a bit more than just "inspiration" from Chrome OS, though, "We're actually using the same code, in some places, and bringing that to mobile."

Android N will now have two system partitions. One will be "online" and used for normal system functions, while the spare one is an "offline" system partition that will sit in the background. With the previous single-partition system, when an OS update came in, the entire phone had to be taken offline for an update. The phone would reboot into recovery mode and apply the update to the system. This can take anywhere from a few minutes to a half hour—Samsung actually quotes "25 minutes" in their update UI. During this time, the user is locked out of their phone calls, texts, notifications, and every other feature of their smartphone.

With Android N's new dual partition system, the online partition keeps running while the OS update is applied to the offline partition in the background. The majority of the downtime processing can happen on the offline partition while the user is still using their device via the online partition.

On the next update, the OS update can be "applied" by just swapping partitions. The updated, offline partition becomes the active one, and since all the processing already happened in the background, there is no recovery mode downtime. The previously active partition becomes the offline one, and it can be brought up to date at the system's leisure (we'd guess in the middle of the night when the phone isn't active).

For end users upgrading from the Android N Developer Preview 3 to something else, the black "Android is updating" screen seen above should be a thing of the past. Previous versions of Android N also added a new compiler that can do JIT (Just In Time) or AOT (Ahead of time) compiling, which allows it to skip the "optimizing apps" dialog after an update and compile the apps later. With both of these changes, applying an update on Android N should be a much faster process than before—it probably won't take much longer than a normal reboot.

This dual partition system should also make updating an Android device safer. Today on Android, if something goes wrong during an update, you've ruined your only copy of the system partition. With no working system partition, your device can't boot, rendering it a useless "brick." It's not a very common occurrence, but even on Nexus devices an update goes wrong sometimes. There is no recovery option for novices—resurrecting the device involves diving into a subset of the Android developer tool package and doing some advanced command line work.

Now, like on Chrome OS, the double system partitions give you redundancy in the case of a failed update. While running on system A, Android will apply an update to system B. On reboot, the bootloader will swap partitions and try to boot from system B. If the boot up fails, you can just restart the phone and the bootloader will switch back to the working system A. Android can then connect to the Internet and work on fixing the unbootable partition by applying the update again.

There is naturally a worry about the storage cost of doubling up on the copies of the system partition on a device. In Android N, system partitions are stored using the highly compressed SquashFS filesystem. SquashFS is designed for an embedded system where space is at a premium, so it should help cut down on some of the storage use. How much storage this all takes in total is definitely something to investigate. We'll have to wait for a working dual-partition build of Android N for exact storage numbers.

With Nexus devices and a few other flagship phones now getting updates every month, Android actually updates more frequently than Chrome OS. Borrowing Chrome OS' faster, safer, more seamless update system is nice. We just wish more devices actually had the first world problem of having to wait for an update to apply.