To get started, go to your smart assistance menu and select smart key.
Here the setup process will be obvious so I'll skip that and let you know what I've been using the smart key for.
One Press activates my flashlight. I often go for a walk around the woods at night and I need to be able to see what's going on without fumbling around with my phone too much. Smart key is a perfect solution.
Double Press is set to open Snapchat simply because it's the app I use most often. It's common to have a shortcut button to your camera app but now I can launch straight into Snapchat.
Press and Hold is set to launch my Google Driving app. This app will automatically start navigating home when you launch it. So when I'm driving, all I have to do it press one button on my phone to start the navigation back to my house. I don't even have to look at my phone screen.
What are you using Smart Key for?