Although the Leanback UI on the NVIDIA Shield TV is designed to be easy to control using a DPAD, this may create some limitations that users don’t want. This led a group of XDA Developers to create a full Android ROM, turning your Shield TV into effectively a huge tablet.
The video goes through the steps of setting it up. It’s a lot like flashing any other Android ROM if you’ve done that before.
The ROM is a version of Android 5.1, although it shouldn’t be too difficult to upgrade to newer versions since a lot of the work is already done. The Android TV versions of the apps can still run fine, and you also get the ability to run Google Play and similar apps without problem. The developers did a solid job of making sure a lot of Android TV features are still available such as support for the Cast Receiver (which you can sideload) while also being able to use advanced customization tools like Xposed.
That’s not to say there aren’t some limitations. NVIDIA’s stock controller uses proprietary tech to send commands wirelessly, meaning that it will only work when it’s plugged in via USB. However, using other types of game controllers will work fine. Bluetooth headsets will provide Bluetooth audio without issue with the additional benefit of having “OK Google” always listening.
The interface for Android phones is not very suitable for a TV, so users will probably want to connect a USB or Bluetooth mouse and use that for navigation. There’s definitely a few quirks, although hobbyists may appreciate the trade-offs for the benefits they get in return. If you’re one of them, head to the XDA Developers thread to learn more.