Just log in from a web browser. 
Once you are logged in, a Dashboard link becomes available in the menu. And the third button on the home page under Web changes from ‘Login’ to ‘View Dashboard’.
The Android app and TV app or only for those respective devices, but the web app will work on any device with a modern web browser.
I’m on mobile, so I don’t have the setup GIF handy, but here’s a GIF of it in action:
https://community.smartthings.com/uploads/short-url/u1g05HtcvMLBIIpVn3zUe3pBQ7Z.gif
Edit: here’s a setup GIF in another thread. There’s a dashboard customizer now, so the setup process is slightly different now, but it gives you the gist: