I have my Pixel 3 magnetically attached to my keyboard, to the left side, next to the tab, caps lock and other keys. It displays a webpage of a grid of buttons which do things when I press them, like inject the current timestamp at the cursor position, toggle my monitors on and off, launch certain apps.

Because I wanted an Elgato Stream Deck but then thought that I have this unused phone.

Can you write up how you set that up? It sounds intriguing.