Update (1/30/20 @ 12:45 PM ET): The ADT-3 Android TV device is now available to purchase for $79.
Android runs on over 2.5 billion devices around the world. Most of those devices are smartphones, but there are also millions of smartwatches, tablets, televisions, and set-top boxes. Android for TVs and STBs, also called Android TV, is much more tightly controlled by Google than Android for smartphones. Manufacturers of TVs and STBs, along with operators, aren't allowed to make many modifications to the core Android TV experience, so what you see with each new release of Android TV is basically what you'll get on any given device. Today, Google announced the Android 10 update for Android TV along with a new testing device for developers - the ADT-3.
Android 10 on Android TV
Google announced the stable Android 10 update for smartphones back in early September, but they held off on announcing the update for TVs. That's because the Android version customized for TVs operates under a different release schedule. However, Android TV is still based on AOSP, so the move to a new OS version brings with it several under-the-hood changes that apply to both smartphones and TVs. Notably, Android 10's new security and privacy features, such as the introduction of TLS 1.3, will help secure user data from malicious apps built for the platform. Project Mainline support will enable Google to serve updates to key framework components directly from the Play Store - bypassing the need for OEMs/operators to push an update. Features like Live Caption, currently a Pixel smartphone exclusive, could be implemented on TVs since the underlying API is part of the Android framework.
In the press release, Google didn't note any Android TV-specific UX changes or new features, so this announcement may seem a bit underwhelming. I would argue that that's a good thing, though. Thanks to reduced fragmentation, Android TV doesn't need major OS upgrades to introduce new features and experiences, unlike on Android for smartphones. Developers can take advantage of Android 10's new APIs by targeting API level 29 in their apps.
ADT-3 Developer Device
In order to properly develop for the platform, developers need a test device running the latest OS version. The ADT-2 was announced at Google I/O 2018 as a testbed for Android 9 Pie, and the new ADT-3 is, as you might expect, a testbed for the new Android 10 release. It's a small set-top box with a quad-core A53 CPU, 2GB of DDR3 memory, and 4K60 HDR HDMI 2.1 video output. It's been pre-certified to run Google apps and services, and it's guaranteed to receive updates and security patches from Google. The device will be sold to interested developers through an OEM partner in the coming months.
In mid-September, Google shared a preview of the Android 10 OS release (and their roadmap for the next two Android versions) at the annual International Broadcasting Convention (IBC). This presentation was given to TV/STB manufacturers, operators, and content providers, but it provides a nice overview of Google's long-term plans for the platform. Google is clearly invested in the success of their TV business, though we wish the same could be said for their smartwatch ecosystem.
Update: ADT-3 On Sale
Google's Android 10-based Android TV device for developers is now available to purchase. The device is being sold through Askey, which is a subsidiary of ASUS Computers. The ADT-3 is available in the US as well as Australia, Austria, Belgium, Canada, Czech, Denmark, Finland, France, Germany, Hong Kong, Hungary, India, Italy, Japan, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Singapore, South Korea, Spain, Switzerland, and the United Kingdom.
While there's nothing stopping consumers from buying and using the ADT-3, the store listing says the device should "only be used by developers." Google has confirmed that the ADT-3 is not certified for Netflix or Amazon Prime Video, so this device definitely isn't meant for media consumption. There are better options out there for consumers when you consider it's $79 and an extra $15 for shipping.
Source: Askey (US), Askey (other regions)