While a video published last week teased it, NVIDIA's new (kind of) Shield Tablet K1 officially made its Marshmallow debut today - the update is available right now. NVIDIA just published an announcement on its forums, from which we've excerpted the changelog you see below.
This update for SHIELD Tablet K1 upgrades the Operating System to Android version 6.0
NVIDIA SHIELD Camera
New UI inspired by Material Design, improved burst photo functionality
Adds new real-time HD Image Effects
Now on Tap
Quickly find information related to what you are seeing on the screen, also from inside an app
MicroSD cards can be integrated with main internal storage, auto managed by system
User Interface Upgrades
Personalize Home & Lock screens with different wallpapers, new NVIDIA wallpapers
Google Now voice commands can be launched from lock screen
Improved App Permissions
Permissions are now managed centrally
App Standby power improvements
Improved BT Low Energy scanning power efficiency
System wide improvements including
Monitor Memory Usage with detailed usage of each app
Optimized preloaded apps
Adds Fallout Shelter game
IMPORTANT: IF YOU ARE CURRENTLY USING A MICROSD CARD IN THIS SHIELD TABLET: In Android 6.0 there are changes to how expanded storage works. After this upgrade, there will be 2 ways to setup the MicroSD card, please read carefully.
Portable Storage: This option will not delete data from the SD card
Internal Storage: This option wipes all data from the SD card. If you are currently storing data the SD card, please make sure it is first backed up
NVIDIA recommends to back up the MicroSD card prior to downloading this update
The update comes with everything you'd expect of Marshmallow, but the big warning about SD cards at the bottom is definitely something to take note of. Marshmallow allows you to "adopt" SD cards as if they were your part of your device's internal storage, but if you've already got an SD card you've been using with your Shield Tablet, you'll need to format it in order to use this new feature.
Outside Android 6.0's built-in features, NVIDIA claims to have revamped the camera app's UI with a more "material"-inspired theme and some new real-time image effects. There are also fresh NVIDIA-designed wallpapers, and Fallout Shelter is now a preloaded app for some reason.
You can get the update by simply checking for it on your Shield Tablet K1 right now. A post from an NVIDIA rep on the forum claims that the Marshmallow update for the standard Shield Tablet will be available "soon."