One of the more exciting - and yet not so much talked about - features of Android 7.0 Nougat is seamless updating. This concept was originally taken from Google's own Chrome OS. It's a way of streamlining how quickly the latest version of the Android OS, either a security patch, an quarterly interim update or a whole new version of the operating system is applied. One of the reasons why we've not seen much about seamless updating is because the feature hasn't been implemented with the current Nexus devices; the reason for this is because it would require connecting the devices up to a computer to repartition internal storage, which Google did not want customers to go through. However; this is Android and inquisitive developers have taken a look into the Android Nougat code to see how it works.
First, a few words about the structure of an Android device's internal memory. Android devices have a number of partitions present on the device, such as /system (where the operating system resides) and /data (where the accessible part of the device lives), plus others including /boot, /recovery and /cache. This is how the device is organized and the operating system prevents us from accessing several of these partitions by default, unless we root our our device. Rooting allows access to the whole internal storage, so applications are able to dip into those previously secured partitions. Current devices perform system updates onto the /system partition, but need exclusive file access to this part of the device; this is why we see the little green Android on his back for several minutes during the update process. Seamless updates removes this delay because the Android device maintains two operating system partitions and applies operating system updates to the unused partition. Then, when it has completed, it asks the user to reboot and as a part of the boot process. Chrome OS' seamless updating technology works by swapping partitions out during the reboot process. The result is that a version update takes at most twelve seconds of the user's time, and that's for a slow Chromebook. More powerful Chromebook models reboot in about half this time.
This is exciting from the perspective of keeping our devices updated and not having to spend several minutes watching as our smartphone updates itself. It stands to reason that after some development work, custom ROMs will also be able to use the same seamless updating technologies. However; there's more, as over on the XDA Developers website, curious developers believe it would be relatively straightforward to design a dual boot device. This might involve removing the seamless Android update technology to make way for another operating system to reside in the second /system partition, but it could make it very easy to switch between different platforms. We've already seen dual, or multi-boot, Android devices in the shape of the MultiROM project, whereby it's relatively easy for devices to boot up into different operating systems. However, running a dual partition device could make this much easier and simpler.
Some might wonder what the second operating system could be? There are several Linux based distributions that work well on a smartphone, and perhaps with development we could see the rumoured Snapdragon 821-powered Pixel or Pixel XL able to host a desktop based operating system. Or we may see Google's new operating system, not based on Linux and called Fuchsia, hacked onto existing Pixel devices - or even officially installed. However, given that this is bleeding edge technology and that messing about with partitions is risky business, it's possible that after launch it will take several months before we are close to implementing a dual boot Pixel-branded device, or for that matter a device running Android 7.0 Nougat out of the box.