The day Glass Explorers have been anxiously awaiting is finally here, and just in time for the open registration event! After a lengthy 4-month wait, XE16 has emerged and transcended its potential vaporware moniker to became a reality. As we've already learned, this latest installment includes a massive version bump to KitKat, photo bundles, photos in Hangouts, sorted voice commands, and much more.

Warning, it looks like everything on Glass will be deleted during the update to XE16. Make sure to back up photos and videos, and be prepared to reinstall any non-official apps. Official Glassware will reinstall itself automatically after the update. We're not sure if there are any adverse effects for rooted users.

Installing the update is pretty similar to previous versions, but with one difference: you'll need to do it twice. The first step is a minor version bump to XE12.1, which serves to do little more than prepare Glass for the real update. It takes about a minute to install and restarts Glass after it has finished. Once rebooted, XE16 will be detected and downloaded after a few minutes. This update takes around 5 minutes to install and reboots once during the process. You'll definitely want to keep Glass plugged in the whole time.

There's a chance that Glass Home and a few other services may crash when everything is done. Just clear the notifications or reboot again to get everything working smoothly.

Google has posted the official list of changes here, but Explorers may also want to check out the thread in the private community. One thing that wasn't mentioned elsewhere is that there are some potentially breaking changes to the GDK (Glass Development Kit). Developers can dig through those details in the changelog on Google's Developer Portal for Glass.

After the update has been installed, it's incredibly clear that the upgrade to KitKat brought some significant speed increases, smoother frame rates, and some new animations. But don't take my word for it, try it for yourself!

There's a ninja update coming out, btw. It won't show up any different from the Glass interface, but it is listed as build XRV15C. You can check your device by connecting to a computer and issuing the command:

adb shell getprop ro.build.id

Update [4/16]: Heads up, there's a hotfix rolling out to Glass units, right now. No changelog has been posted, but this is likely in response to pretty severe battery drain introduced with the latest update. Yes, we see the irony, too. The new build number is XRV15C, replacing XRV15B from yesterday. This is a ninja update, so you won't be prompted to install, it will simply download and restart Glass automatically. Chances are good that it has already happened and you won't even notice it. There are no visible indicators of build number on Glass's interface, but you can check to see if yours has updated by connecting to a computer with the latest version of ADB, open a command prompt, and enter: 'adb shell getprop ro.build.id'.

Source: Glass Community (explorers only), XE16 Release Notes, XE16 Developer Release Notes