Putting Android on things has become the new putting Linux on things.
The Nintendo Switch was never meant to run Android. It's a portable game console with a 6.2-inch 720p display powered by the Tegra X1 chipset (which is also found in the NVIDIA SHIELD Android TV), 4GB of LPDDR4 RAM, and a 4,310 mAh battery. It runs games like The Legend of Zelda: Breath of the Wild, Super Mario Odyssey, and Mario Kart 8: Deluxe. Those specifications make for a pretty beefy handheld games console, but imagine an Android tablet with those specifications? That's effectively what we've got here thanks to ByLaws and fellow developers, and while it's certainly not perfect yet, it's already pretty powerful.
One of the most appealing aspects of the Switch is the fact that it is a hybrid console. When you put it in the Switch dock and detach the controllers on the sides, it becomes a full-fledged console with 1080p output via HDMI and higher CPU and GPU clock rates. When you're done, just re-attach the controllers, take the Switch out of the dock, and use it wherever. A similar idea was employed by the NVIDIA SHIELD Tablet, an Android gaming tablet that could output to a TV at up to 8K resolution. Android on the Switch works in the same way as it once did on the NVIDIA SHIELD Tablet. Dock your Switch and it will output the display via HDMI, where you can continue to use it as normal on a bigger screen. The Switch dock also has 3 USB ports which you can plug a keyboard, mouse, and another peripheral into. At the moment, USB mass storage mounting does not work.
Other than that, Android on the Nintendo Switch works just like a tablet.